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Item Métodos diagnósticos para o vírus mayaro: revisão sistemática e avaliação molecular em pacientes arbovirose like em unidade municipal de sáude de Goiânia-Goiás(Universidade Federal de Goiás, 2020-02-17) Abrantes, Gabrielly Regis; Anunciaçāo, Carlos Eduardo; http://lattes.cnpq.br/4354412874919580; Lacerda, Elisângela de Paula Silveira; http://lattes.cnpq.br/9390789693192751; Lacerda, Elisângela de Paula Silveira; Anunciaçāo, Carlos Eduardo; Lino, Guilherme; Mrué, FátimaDiseases caused by viruses are considered an often neglected public health problem that affects thousands of people worldwide, every year. Symptoms like fever, arthralgia and rash. classify patients as syndromic dengue or arbovirus like. The differential diagnosis of arbovoresis is by serological and molecular techniques. The present study aimed to evaluate diagnostic techniques in studies published in the literature in order to develop a Systematic Literature Review on the detection of the Mayaro virus that allows health professionals to carry out an efficient laboratory diagnosis, as well as the application of molecular tests for the diagnosis of MAYV. The available literature was evaluated by systematic review, focusing on the diagnosis of the Mayaro virus in humans and its methodologies. The systematic review was carried out through an exploratory study in the databases: Scielo (Scientific Eletronic Library Online), Medline (Medical Literature Analysis and Retrieval System Online), Scopus database, PubMed, LILACS from June 8, 2019 to 02 November 2019, selecting scientific articles according to the criteria of the PRISMA (2009) recommendation. The data showed that the circulation of the Mayaro virus in urban regions is already well established worldwide and that the misdiagnosis is frequent due to similar symptoms with other arboviruses. There is a wide use of varied methods over time in the diagnosis for this arbovirus, requiring further research to implement a standardized, sensitive and specific method. In a second stage of the research, between May to August 2017 and January to June 2018, 452 samples of patients with syndromic dengue symptoms (arboviruses like) were screened. The samples were sent to the Molecular Genetics and Cytogenetics Laboratory of the Federal University of Goiás, where they were subjected to molecular screening by Polymerase Chain Reaction followed by Reverse Transcriptase (RT-PCR) reaction. All positive cases for the first PCR were confirmed on RT-qPCR for viral detection. Thirteen positive samples went through both tests and thus were subjected to Sanger sequencing. In this experimental study, 17 samples were positive for the Mayaro virus infection (RT-PCR and RT-qPCR), and co-infections with the Dengue virus were also found by molecular screening carried out in parallel for the Dengue virus by RT-PCR and RT-qPCR. The positive samples for MAYV / DENV were analyzed phylogenetically, suggesting circulation of Dengue serotype 2 and a Peruvian strain of Mayaro Virus (strain IQ 4235) in Goiânia.Item Estudo filogeográfico de Micrurus lemniscatus (LINNAEUS, 1758) (SERPENTES: ELAPIDAE)(Universidade Federal de Goiás, 2014-03-10) Abreu, Tatianne Piza Ferrari; Silva Junior, Nelson Jorge da; http://lattes.cnpq.br/6544526824923185; Collevatti, Rosane Garcia; http://lattes.cnpq.br/9979596352166630; Collevatti, Rosane Garcia; Maciel, Natan Medeiros; Vaz-Silva, WilianMicrurus lemniscatus is a South American coral snake species, popularly known as “coral verdadeira”. It is widely distributed in Seasonally Dry Forests (SDF), Gallery Forests and Rainforests. The Tertiary events and the climatic oscillations of the Quaternary affected the distribution of these ecosystems altering, in turn, the distribution of animals associated to these habitats. We hypothesize that the forest expansion and contraction cycles caused by climate fluctuations may have influenced the current distribution and genetic structure of M. lemniscatus. This study aimed to study the evolutionary relationships and patterns of divergence among M. lemniscatus lineages and infer the historical biogeographic events that influenced the distribution and genetic variation. Twenty-nine individuals of M. lemniscatus were sampled from 16 localities in the states of Tocantins, Bahia, Goiás, Alagoas, Mato Grosso, Maranhão, Pará and Amazônia. Three mitochondrial regions (COI, 16S and ND4L) were sequenced, and together generated a fragment of 1595 bp and 23 different haplotypes. The analyses showed a very ancient lineage divergence ~ 4.5 Myr and high genetic differentiation among localities (FST=0.932; p<0.01), suggesting a limited gene flow among geographical regions. The demographic analyzes and neutrality tests indicated that there is no sign of expansion and that populations have constant size (Tajima’s D = 0.521; p = 0.763 and Mismatch distribution = 0.009; p= 0.779). In the analysis of the evolutionary relationship between haplotypes (by median-joining network method), no relationship between lineage and geographical space was found, suggesting incomplete lineage sorting. The results corroborate and give evidence that populations of M. lemniscatus were distributed in a more continuous region in the past, and the current distribution of this species may be the result of the reduction and separation of the geographical scope of their distribution, rather than having itself been an expansion event. This may be the result of cycles expansion of SDF and retraction of the rainforests during the cool and dry phases of the Quaternary.Item Bioprospecção de bactérias quitinolíticas e caracterização da atividade da enzima quitinase(Universidade Federal de Goiás, 2018-04-12) Alexandre, Artur Ribeiro de Sá; Amaral, André Corrêa; http://lattes.cnpq.br/8801299423520104; Amaral, André Corrêa; Carneiro, Lilian Carla; Vieira, José Daniel GonçalvesBioprospecting is defined as the search for organisms, genes, enzymes, compounds, processes and any pieces from living beings, that could have economic potential, and eventually lead to a product development. Thus, enzymes, protein catalysts, have aroused the interest of industries for its conversion mode specific biomass, low energy cost and not production of toxic waste. Chitinases are enzymes that catalyze the lysis of chitin (biopolymer composed of N-acetylglucosamine monomers), and thus have several applications, among them: obtaining N-acetylglucosamine monomers, used in the production of prebiotics; degradation of chitinous waste from fishing activities; and the use in control of fungi and insects. The present work aimed to bioprospect chitinase producing bacteria from soil samples and to characterize the enzymatic activity patterns of the best bacterial isolate. To do so, a screening with 17 soil samples collected in the states of Minas Gerais, Santa Catarina and Rio Grande do Sul, was carried out using a culture medium with colloidal chitin. Thirteen chitinase producing bacteria were obtained, among them, the isolate Q1 (identified as Paenibacillus illinoisensis), demonstrated to be a good producer of the enzyme and thus was selected for determination and optimization of its chitinase activity evaluating reaction time, temperature and pH. The chitinase produced by the isolate showed 0.098 U of activity, which was subsequently improved to 0.66 U when tested under the optimal conditions of 1 hour of reaction at 37 ºC and pH 4, an increase of 573% over the initial value. The values of chitinase activity from the isolate P. illinoisensis are close to those found in other studies, which also emphasize the potential application of the enzyme, mainly in the control of phytopathogenic pests. Bioprospecting of chitinase producing bacteria is possible and promising.Item Biologia floral e sistema de autoincompatibilidade de Bauhinia brevipes Vogel (Fabaceae), no município de Goiás, Estado de Goiás, Brasil(Universidade Federal de Goiás, 2014-04-23) Almeida, Elga de Fátima; Franceschinelli, Edivani Villaron; http://lattes.cnpq.br/8863732932277904The plant reproductive biology involves all the features (morphological, anatomical or physiological) of a species that participate in the reproduction of its individuals. The Fabaceae family is one of the most important of the Cerrado, the genus Bauhinia being one of the most diversified. Several studies with species of Bauhinia L. showed diversity in floral shapes, reproductive phenology, reproductive system and interactions with different groups of pollinators. In general, the Bauhinia species are outcrossing and have low reproductive efficiency. Bauhinia brevipes is common in the municipality of Goiás-GO and has floral features compatible with the syndrome chiropterophily: white flowers that release a strong odour overnight, producing large amounts of nectar with low sugar concentration. Flowers of B. brevipes may have reduced ovaries or anthers with low production of viable pollen, indicating that this species moves towards sexual separation in some flowers. Although the visit the bats to flowers were not seen, their flights over the plants were observed. A test of exclusion of diurnal pollinators showed the efficiency of nocturnal pollinators in B. brevipes. The flowers of B. brevipes not have herkogamy as the main factor to avoid inbreeding, but some flowers positioned above the anthers stigma were observed. The species present gametophytic selfincompatibility and therefore requires the pollinators visit to ensure pollinating pollen exchange among different and unrelated plants. Bauhinia brevipes has an average 20% of reproductive efficiency. In general, the species showed a high level of pollen limitation (0.73). The largest fruit production occurs in the middle position of the inflorescence. Most of fruit produced occurs in the median position of the inflorescence, when possibly the availability of pollen in the system is higher and resources are available for their development.Item O envolvimento do núcleo paraventricular do hipotálamo na manutenção da pressão arterial e modulação do tônus simpático renal de ratos tratados com dieta rica em sódio na fase pós natal(Universidade Federal de Goiás, 2019-06-28) Almeida, Melissa Tavares; Mourão, Aline Andrade; http://lattes.cnpq.br/1596884578398481; Pedrino, Gustavo Rodrigues; http://lattes.cnpq.br/1155446449250341; Ferreira-Neto, Marcos Luiz; Mendes, Elizabeth Pereira; Pedrino, Gustavo RodriguesHigh sodium intake can affect the excitability of neurons in regions responsible for the control of sympathetic nervous activity. It is known that the neuronal activity of the hypothalamus paraventricular nucleus (PVN) is increased in several models of sodium-sensitive arterial hypertension (SSH). Diseases that develop in adulthood are related to certain exposures suffered by the individual during the early stages of life. However, the literature point out differences between males and females in the expression of hypertension in both animal and human models, and in females, estrogen sometimes has a cardioprotective effect. In the present study, we investigated whether changes in diet during the postnatal phases contribute to central alterations in the control of renal sympathetic tone in males and females, and whether they persist in adulthood. More specifically, we evaluated the contribution of the PVN in the control of cardiovascular parameters and sympathetic nervous activity (SNA) after treatment with a sodium-rich diet for 30 days in adult rats and rats. Twenty one days old wistar male and female rats were divided into two groups: control group, composed of males (MCTRL) and females (FCTRL), maintained with water; and experimental group, composed of males (MEXP) and females (FEXP), maintained with hypertonic solution of 0.3 M NaCl. Animals of all groups received chow and hypertonic solution or water ad libitum for 30 days. After treatment, the animals of all groups were maintained with water and chow for 15 days (recovery period). Daily food and fluid (0.3 M NaCl or water) intake and body weight were monitored during the treatment and recovery periods. At the end of treatment, the treated male rats were found to have lower body weight compared to controls (MEXP (n = 9): 115.3 ± 4.7 g vs. MCTRL (n = 9): 168.0 ± 8.0 g, p <0.05). However, this difference was not observed between the experimental and control female groups (FEXP (n = 8): 119.5 ± 5.3 g vs. FCTRL (n = 8): 134.1 ± 5.2 g). We also observed that the experimental animals ingested a greater amount of fluid per gram of body weight (bw) than control animals MEXP (n=9): 0.717 ± 0.120 mL/g/bw vs. MCTRL (n=9): 0.209; FEXP (n=8): 0.576 ± 0.060 mL/g/bw vs. FCTRL (n=8): 0.251 ± 0.011 mL/g/bw, p < 0.05) and we observed a decrease in the excreted volume (Vexc) in experimental females compared to the ingested volume (Ving) (FEXP (n=8): Ving 89.6 ± 5.6 mL vs. Vexc 56.8 ± 5.2 mL, p < 0.05). In the recovery period there was no difference in daily water intake between groups (MEXP (n=9): 0.203 ± 0.008 mL/g/bw vs. MCTRL (n=9): 0,171 ± 0.005 mL/g/bw; FEXP (n=8): 0,229 ± 0,013 mL/g/bw vs. FCTRL (n=8): 0.187 ± 0,010 mL/g/bw). In another set of experiments, we evaluated the participation of the PVN in the maintenance of sympathetic tonus after treatment with a high sodium diet for 30 days. Bilateral nanoinjections of 50 nL of muscimol (GABAA agonist, 4 mM) were performed in the PVN in experimental and control animals during recording of mean arterial pressure (MAP), heart rate (HR) and renal SNA (RSNA). It is noteworthy that in the females these experiments were performed in the diestrus of the estrous cycle. In the anaesthetized experiments, the males of the treated group showed higher values of baseline MAP compared to both control male group and to female groups (PAM: MEXP (n=6): 108.2 ± 2.9 mmHg vs. MCTRL (n=6): 92 ± 5.4 mmHg vs. FEXP (n=6): 102.7 ± 4.4 mmHg vs. FCTRL (n=6): 90.8 ± 1.8 mmHg, p<0.05). Inhibition of the PVN promoted a reduction on MAP of experimental groups when compared to control groups: (Δ MAP: MEXP (n=6): -14.9 ± 1.5 mmHg vs. MCTRL (n=6): -7.2 ± 0.7 mmHg vs. FEXP (n=6): -12.9 ± 1.7 mmHg vs. FCTRL (n=6): -4.8 ± 0.6 mmHg, p <0.05). On the other hand, no differences were observed in the HR responses of the evaluated groups (Δ HR: MEXP (n=6): -35.8 ± 6.6 bpm vs. MCTRL (n=6): -21.6 ± 2.9 bpm vs. FEXP (n=6): -27.8 ± 3.5 bpm vs. FCTRL (n=6): -31.0 ± 4.4 bpm). In addition, acute inhibition of PVN promoted renal sympathoinhibition in experimental animals compared to controls (Δ % ANSR: MEXP (n=6): -17.3 ± 1.5% vs. MCTRL (n=6): -6.8 ± 1.0% vs. FEXP (n=6): -18.1 ± 0.5% vs. FCTRL (n=6): -3.0 ± 0.6%, p <0.05). The results demonstrated in the present study showed that the hypersodiuc diet during the early stages of life altered baseline MAP of experimental males. Additionally, we observed that the acute inhibition of PVN promoted cardiovascular and sympathetic changes in rats treated with a high sodium diet in comparison to the control group. Taken together, the observed results add new information to the literature and suggest that cardiovascular and sympathetic control regions, such as the PVN, may be more involved in the tonic modulation of blood pressure and RSNA in response to sodium overload in the postnatal phase of normotensive rats. Finally, our study points to the possibility that estrogen may have helped decrease the high blood pressure promoted by prolonged increase in sodium intake, but it was not enough to prevent the increase in the modulation of the sympathetic tone exerted by the PVN. However, future studies are needed to investigate pathways and mechanisms involved in these responses.Item A Teoria Neutra pode explicar a diversidade de insetos aquáticos em riachos?(Universidade Federal de Goiás, 2009-04-07) ALMEIDA, Mirian Cristina de; MARCO JÚNIOR, Paulo de; http://lattes.cnpq.br/2767494720646648The generality of Unified Neutral Theory of Biodiversity and Biogeography was evaluated across its support for diversity structure of Odonata adults and predators, shredders and collectors insect guilds in streams. The evaluation of Neutral Theory was done in two levels of theory s hierarchical structure. One evaluation in the level of yours assumptions, the zero sum assumption, and other in the level of yours predictions to abundance models in communities and metacommunities, ZSM and logseries respectively. The variations predicted to ZSM abundance model, in accordance to dispersal limitation that community are subjected, was evaluated in insect guilds through the streams distance. In Odonata adults the dispersal limitation was evaluated indirectly through regional frequency of species body size. In this case, the ecological equivalence was restricted for body size guilds. Communities of Zygoptera adults have low density and richness within streams. Individuals distribution was grouped, not consistent to linear relation under zero sum assumption. Local abundance of Odonata adults and predators, shredders and collectors guilds didn t fit ZSM model. Geometric series models and logseries models were better in explain the abundance for all groups. Moreover, the occurrence of fit to these models isn t in according to dispersal limitation level that is expected in each region, not supporting the Neutral predictionsItem Relação entre capacidade de dispersão, tolerância ambiental e tamanho da distribuição geográfica em Artibeus (Mammalia, Chiroptera)(Universidade Federal de Goiás, 2020-02-27) Almeida, Rafaela Gonçalves; Marco Júnior, Paulo De; http://lattes.cnpq.br/2767494720646648; Diniz Filho, José Alexandre Felizola; Oliveira, Arthur Angelo Bispo deThe species’ dispersal ability is relate to several ecological processes, such as the establishment of new populations, and may be associated with species responses to environmental changes. However, direct measurements of this parameter are difficult to obtain, so that several studies use morphological data as surrogate of dispersal ability. In this study, we tested whether bat species of the genus Artibeus with greater dispersal ability have greater geographic distribution and tolerance limits. We used morphological data available in the literature, represented by forearm size, body weight, Relative Wing Loading (RWL) and Aspect Ratio (AR). We calculated the geographical range size for species with morphological data available in the literature. We estimated the limits of environmental tolerance through the Outlying Mean Index (OMI), based on the species geographical range and a set of environmental variables. We used Phylogenetic Generalized Least Squares models (PGLS) to control the phylogenic effect in our analysis. Species with higher RWL showed higher environmental tolerances, while no morphological measures influenced the geographical range size or the environmental tolerance. High RWL values could facilitate individual’s flight over long distances, exposing them to greater variations in environmental conditions, and leading to an increase in environmental tolerance. The low predictive power of the dispersal ability in relation to the area may be related to the variation of the environmental heterogeneity within the limits of the species distribution. Finally, we emphasize that the RWL can be a good dispersal ability surrogate, as it considers several morphological parameters of the Artibeus’ species.Item Análise da comunidade de peixes e da teia trófica de um trecho do rio corrente - go(Universidade Federal de Goiás, 2006-07-18) ALOÍSIO, Gustavo Ribeiro; ANGELINI, Ronaldo; http://lattes.cnpq.br/6739463859587165In this work, fishes of Corrente river, affluent of Paranaíba River (Paraná basin, Brazil), were studied. Five surveys in the period of June of 2003 had been carried out until June of 2005. The sampling was executed in 8 points distributed in the stream, riverbed and lagoon. In each point had been used a set of gillnets with different mesh size (between 12 and 60mm opposite knots). The nets were inspected in the morning and the end of the day. The results had shown that 8 species were captured and the most abundant specie is Astyanax altiparanae; Shannon-Wienner index demonstrated diversity low; Morisita index indicated that there are high similarity between river, stream and lagoons; all species reproduce in the rainy season with exception of the Brycon nattereri; it is demonstrated the existence of piscivores species, herbivores, insectivores and detritus feeders.Item Efeitos diretos e indiretos de características de plantas sobre a similaridade na composição de insetos herbívoros e parasitoides associados à Asteraceae(Universidade Federal de Goiás, 2018-03-15) Alvarenga, Vinícius Silva de; Almeida Neto, Mário; http://lattes.cnpq.br/1000297113793647; Almeida Neto, Mário; Santos, Carolina Moreno dos; Araújo, Walter Santos deUnderstanding how interactions between trophic levels structure species composition is one of the main goals of ecological studies. Mechanisms that explain the compositional structure of parasitoid insects usually neglect the direct and indirect effects of plants’ characteristics, which can also determine the compositional structure of their host herbivore insects. In this context, our goal was to evaluate how plants’ characteristics (abundance, floral phenology, and phylogenetic distance) and herbivores’ compositional similarity determine parasitoids’ compositional similarity. As study system, we used Asteraceae species, flower-head feeding insects, and parasitoids. Using path analysis, we considered parasitoids and herbivores’ similarities, in qualitative (Sørensen similarity), quantitative (Bray-Curtis similarity), and phylogenetic proximity (taxonomic Sørensen similarity) terms. In general, we demonstrated that herbivores’ similarity is the major predictor of parasitoids’ similarity. Even though the effects of plants’ characteristics explained the smallest part of the variation in parasitoids’ similarity, these characteristics had inconsistent relative importance among the similarity indexes used here. Thus, our results indicate that although plant species constitute a potential additional barrier for the parasitoids of endophagous herbivores to find their insect hosts, herbivore parasitoids in flower heads of Asteraceae do not see the plant species in this way. The parasitoids respond mainly to the compositional variation of their insect hosts in the plant species that the latter consume. Therefore, we show how the composition of the upper trophic levels in this tri-trophic system is structured directly and indirectly by antagonistic interactions.Item Análise de polimorfismos em genes de detoxificação e reparo em indivíduos de municípios goianos(Universidade Federal de Goiás, 2017-03-10) Alves, Alessandro Arruda; Silva, Daniela de Melo e; http://lattes.cnpq.br/9895211901348365; Soares, Thannya Nascimento; Rodrigues, Flavia MeloIn Brazilian agriculture, the State of Goiás is one of the largest producers of corn, beans, cotton, sorghum, sugarcane and soybeans, with 75% of its exports composed of products related to agriculture and minerals. Thus, a large part of the economy of the State of Goiás is focused on rural activities, justifying the intense use of pesticides in the region. These pesticides will be metabolized in the liver in two main phases, the first one of bioactivation converting the original substances into more polar metabolites, through oxidation reduction reactions, hydrogenation and dehalogenation, most of the reactions are made by the cytochrome P450 (CYP) superfamily And the second phase in which conjugation reactions occur, in which metabolites are converted into non-toxic products. Agrochemicals are also known to cause various human health damage, such as cancer, cholinergic syndrome, Parkinson's disease and Alzheimer's as well as cytogenetic changes such as DNA damage and chromosome translocations. Thus, polymorphisms in enzymes acting in the path of detoxification and DNA repair may be important biomarkers of diseases in individuals exposed to pesticides. The present study sequenced 3 regions of the following genes: CYP2E1 (promoter region), CYP1A1 (exon 7) and OGG1 (intron region) of 260 individuals from Goiânia and Aparecida de Goiânia, GO. 20 ml of blood was collected, DNA was extracted using commercial kits and PCR was performed. Subsequently, the amplicons were sequenced by the automated Sanger method and compared to the 1000 Genome project. The population of this study was composed of 159 men and 101 women, mean age of 38 years. A total of 5 SNP's were found in the Goias population, being rs2031922 (change of C> T and frequency of the T allele of 0.05) of the CYP2E1 gene, rs1048943 (change of A> G and frequency of the G allele of 0.1 ) And rs1799814 (change of C> A and frequency of allele A of 0.07) of the CYP1A1 gene and rs1052133 (change of C> G and frequency of allele G of 0.2) and rs293795 (change of A> G and frequency Of the 0.18 T allele) of the OGG1 gene. All loci did not deviate from the Hardy-Weinberg equilibrium, nor was a statistically significant difference between age and genotype composition. The rs1048943 and rs1799814 loci of the CYP1A1 gene showed a moderate disequilibrium linkage and the rs1052133 and rs293795 loci of the OGG1 gene showed a strong disequilibrium linkage. The haplotype inference revealed a frequency of the haplotypes of loci rs1048943 and rs1799814 of A / C = 0.8, G / A = 0.12, A / A = 0.07 of the CYP1A1 gene. The haplotypes of the loci rs293795 and rs1052133 had A / G = 0.07, A / C = 0.8, G / C = 0.13. Due to the important participation in detoxification or DNA repair and relationship with pesticides, SNPs rs2031920 of the CYP2E1 gene, rs1048943 of CYP1A1 and rs1052133 of the OGG1 gene are potential biomarkers of susceptibility to disease development in individuals who have contact with these xenobioticsItem A dinâmica do fitoplâncton em uma várzea Amazônica variações sazonal e nictimeral (Várzea do Lago Grande de Curuai Pará, Brasil)(Universidade Federal de Goiás, 2011-03-28) ALVES, Carla Patrícia Pereira; NOGUEIRA, Ina de Souza; http://lattes.cnpq.br/3877834258990173The river-floodplain systems are environments submitted a lateral overflow of river channel due the rains and/or underground waters. They are controlled by the type of climate, morphology and local effects. The lowland lakes are also highly productive because of the rich sources of primary carbon. The sediments transport and suspended and dissolved matter are done by the rivers between the land and aquatic phases. These phases strongly influence nutrient cycling, primary and secondary production and decomposition. The phytoplankton dynamics in tropical floodplain lakes is as variable as the seasonal and isolation patterns of flooding. For this reason, the aims of this work were i) to assess the rotation influence of potamophase and limnophase upon the phytoplankton of the Curuai Lake (PA, Brazil) and about the connectivity between other lakes, and ii) to evaluate the phytoplankton dynamics in a nictemeral cycling related to changes in CO2 in water, and what phytoplankton groups which were most important in this process. The phytoplankton community and environmental variables of the floodplain lakes of the Curuai Lake were sampled in the potamophase and limnophase (2009) and in a nictemeral cycling (2010). The informations summarized were obtained through the principal component analysis (PCA), canonical correspondence analysis (CCA), redundancy analysis (RDA) and nonmetric multidimensional scaling (MDS). The community structure was different among the periods with greater richness, density and phytoplanktonic biovolume in limnophase. There was predominance of Cryptophyceae (mainly Cryptomonas brasiliensis Castro, Bicudo & Bicudo) in potamophase and Cyanophyceae [Dolichospermum circinalis (formerly Anabaena circinalis) (Rabenh. ex Bornet et Flah.) Wacklin et al.] in limnophase, both influenced by environmental variables. In addition, the high phytoplanktonic biomass was favored by the highs temperatures and also responsible by the CO2 depletion in water caused by photosynthesis, which is reflected for the high carbon content in phytoplankton organisms. Despite the entry of water in the floodplain that connects the lakes, these environmental were distinct in relation a phytoplankton composition and a limnological variables. The phytoplanktonic community in Curuai Lake showed daily variation of biovolume because of high temperature and light availability. The development of persistent cyanobacteria bloom, with species predominance of Dolichospermum genius [functional group H1, D. spiroides (formerly A. spiroides) (Klebahn) Wacklin et al.] and Microcystis protocystis Crow (functional group M) caused the CO2 depletion in lake surface layer during the period of increased photosynthesis. The cyanobacteria bloom occurred mainly due to the attributes of group, which became it expressive competitors in relation another microalgae ones.Item O impacto da síndrome do nariz-branco no estado de conservação dos morcegos norte-americanos(Universidade Federal de Goiás, 2013-12-18) Alves, Davi Mello Cunha Crescente; Brito, DanielThe White-Nose syndrome is an emergent infectious disease that had already killed almost six millions North American bats and spread more than two thousand kilometers. Even so, studies about their possible impacts upon hosts are still lacking, principally upon all the susceptible North American bats. We predicted the consequences of the WNS spread in the North American hosts by generating an environmental suitability map for the disease, and then, we overlaid with the extension of occurrence of all hibernating bats in North America. We assumed that all intersection localities will somehow negatively affect bat’s local populations, and we reassessed their conservation status based on their potential population reduction. 16% of the North American hibernating bat fauna were considered threatened under this WNS potential spread. We believe our results could contribute with governments conservation actions.Item Padrões geográficos e temporais na riqueza de espécies de quirópteros: mecanismos ecológico-evolutivos e incertezas(Universidade Federal de Goiás, 2017-04-10) Alves, Davi Mello Cunha Crescente; Villalobos, Fabricio; http://lattes.cnpq.br/9691616509605593; Diniz-Filho, José Alexandre Felizola; http://lattes.cnpq.br/0706396442417351; Diniz Filho, José Alexandre Felizola; Ribeiro, Matheus de Souza Lima; Rangel, Thiago Fernando Lopes Valle de Britto; Teresa, Fabrício Barreto; Quental, Tiago Bosisionão consta.Item Caracterização de proteases secretadas por Sclerotinia sclerotiorum(Universidade Federal de Goiás, 2019-05-25) Alves, Elda Bueno; Silva, Silvana Petrofeza da; http://lattes.cnpq.br/6823998544968373; Silva, Silvana Petrofeza da; Andrade, Rosangela Vieira de; Faria, Fabrícia Paula deSclerotinia sclerotiorum is a fungus that infects many economically important plants. The production of oxalic acid, decreased the pH of the medium and the secretion of hydrolytic enzymes such as proteases, are determining factors for the infection of this pathogen. Proteases secreted by the fungus S. sclerotiorum degrade the cell wall proteins of the host and antifungal proteins secreted by the plant during the invasion. This study aimed to characterize molecular and biochemical proteases in S. sclerotiorum, during the invasion in bean plants (Phasheolus vulgaris L.) and in culture medium supplemented with pectin, the wall of bean extract and glucose as carbon sources. The secretion of these proteases was detected by enzymatic assays with specific inhibitors and buffered media at different pH. The level of expression of genes encoding for the protease aspartyl (aspS) and acid protease (acp1), respectively, were detected by qRT-PCR technique. Enzyme activity was detected in all sources of carbon, but higher levels were found when pectin was used as the sole carbon source. Tests with different proteolytic inhibitors showed that Pepstatin A specific inhibitor for aspartyl protease-inhibitor that has been the greatest action in culture media, indicating the probable secretion of aspartyl proteases. Of qRT-PCR experiments showed that the expression of genes aspS and acp1 was increased in S. sclerotiorum both in culture medium supplemented with pectin or extract of the cell wall of bean, as during the infection in bean seedlings. These results suggest that the fungus secret proteases during the infection of the host plant. And the different carbon sources evaluated, similar to components of the cell wall of host plants, are effective for the induction of gene expression (acp1 and aspS) in S. sclerotiorum. Thus, the proteases have been considered an important virulence factor in increasing the efficiency of fungal attack in plants.Item Respostas bioquímicas e fisiológicas de mutantes fotomorfogenéticos de tomateiro (Solanum lycopersicum L. cv. Micro-Tom) sob deficiência hídrica(Universidade Federal de Goiás, 2015-02-26) Alves, Frederico Rocha Rodrigues; Melo, Hyrandir Cabral de; http://lattes.cnpq.br/9055607630353419Phytochrome-dependent physiological processes are being unveiled by photomorphogenic mutant plants. In tomato (Solanum lycopersicum L.), the aurea mutant is phytochrome-deficient and the high-pigment 1 mutant (hp1) has exaggerated light responses. Phytochromes are related to many abiotic and biotic stress responses due to its role in the regulation of specific genes transcription, acting upon biochemical and molecular mechanisms of cell signaling. Here, we examined the effects of water-withholding over water potential, leaf gas exchanges, chlorophyll fluorescence parameters and chloroplast pigments content in photomorphogenic tomato mutants aurea and hp1, as well its wild-type cultivar Micro-Tom (MT). The plants were grown in a greenhouse under controlled conditions of temperature (24-27ºC) and humidity (60-70%). Analysis were made in 35-days-old plants (n=5) which irrigation was suspended for 5 days and then rehydrated in the sixth day. As control, five plants of each genotype remained well-watered. Water-withholding decreased the water potential and affected leaf gas exchange rates in all studied genotypes, decreasing rates of photosynthesis and stomatal conductance from the fourth treatment day on. Initial fluorescence and PSII potential quantum efficiency were not affected by the water-withholding treatment in general, but MT showed significant decrease in PSII operating efficiency and electron transporte rate as well as an increase in non-photochemical quenching parameters, facts not registered for the mutants during the treatment period. hp1 mutant has the highest content of chlorophyll a, chlorophyll b and carotenoids, this last playing a central role in the oxidative stress defense. Under water-withholding conditions, MT presented the highest MDA concentration and aurea displayed high activities of catalase, peroxidase and ascorbate peroxidase when compared to the other genotypes. The present data allows the conclusion that the mutants have higher tolerance to drought stress than the wild Micro-Tom genotype.Item Avaliação dos efeitos de peptídeos isolados de veneno de serpentes no sistema cardiovascular de ratos(Universidade Federal de Goiás, 2016-03-22) Alves, Pedro Henrique; Ianzer, Danielle Alves; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4760882T6; Alves, Carlos Henrique; http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4758015Z0; Castro, Carlos Henrique de; Ianzer, Danielle Alves; Ghedini, Paulo CesarThe proline-riche-oligopeptides (PROs) were identified in the crude venom of snakes Bothrops jararaca (Bj), Bothrops cotiara (Bc) and Bothrops fonsecai (Bf). Previous studies have shown hypotensive/antihypertensive effects of the PROs in normotensive and hypertensive (SHR) rats. However, the direct effect of PROs in the aorta and heart isolated, as well as, the action mechanisms involved in these effects is unknown. In the presenty study, were evaluated the cardiovascular effect of six PROs, Bj-PRO-5a,-7a,-10c, Bc-PRO-10e, Bf-PRO-10d,-10f. The aortic rings, with (E+) or without (E-) endothelium, were preconstricted with phenylephine (Phe, 0.1 μmol/L), following increasing concentrations of PROs (0.1 nmol/L – 1 μmol/L) in presence or absence of a nonselective antagonist muscarinic receptors (Atropine, 3µmol/L), M1 muscarinic receptor antagonist (Pirenzepine, 1 µmol/L), synthase nitric oxide inhibitor (L-NAME, 1 µmol/L), adenylyl cyclase inhibitor (MDL 12.330A, 3 µmol/L), guanylyl cyclase inhibitor (ODQ, 3µmol/L) or argininosuccinate synthetase inhibitor (MDLA, 1 µmol/L). To evaluated the coronary and cardiac contractility effects of PROs, the hearts were perfused according Langendorff technique. The hearts were perfused for a basal period with Krebs Ringer solution containing the PROs (0.05 or 5 nmol/L) in presence or absence of L-NAME (10 nmol/L), ODQ (200 nmol/L) or MDL (1 µmol/L). The PROs utilized in this study induced endothelium-dependend vasorelaxation in aortic rings of Wistars and SHRs. Atropine and pirezenpine blocked the vasorelaxant effect of Bj-PRO-7a in isolated aorta from Wistar and SHR. L-NAME, ODQ or MDL inhibited the aortic vasorelaxation induced by Bj-PRO-7a and Bj-PRO-10c in both strains. MDLA inhibited the Bj-PRO-10c-induced vasorelaxation in aortic rings of SHR, but not in Wistar. Just the peptides Bj-PRO-7a and Bj-PRO-10c promoted a significant coronary vasodilatation in isolated heart from Wistar and SHR rats. The coronary vasodilatation induced by Bj-PRO-7a was inhibited in the presence of L-NAME in isolated heart from Wistar. Already in isolated heart from SHR this effect was abolished by L-NAME, ODQ or MDL. The Bc-PRO-10e and Bf-PRO-10f did not induce significant effects on cardiac contractility. However, the Bj-PRO-5a, -7a, -10c and Bf-PRO-10f promoted negative inotropic effect in the isolated hearts from Wistar and/or SHR. This effect in isolated hearts perfused by Bj-PRO-7a was inhibited in the presence of L-NAME in Wistars. Differently, the effect of Bj-PRO-10c was blocked by L-NAME, ODQ or MDL in both strains. Sumarizing, the PROs utilized in this study induced endothelium-dependend vasorelaxation. The data demonstrated participation of pathways NO/GCs/GMPc and AC/AMPc in the vasorelaxant effect of peptides Bj-PRO-7a and Bj-PRO-10c. In addition, the muscarinic receptors are involved in the vasorelaxant effects induced by peptide Bj-PRO-7a in aortic rings from Wistar and SHR rats. Moreover, the negative inotropic effect induced by Bj-PRO-7a and Bj-PRO-10c is linked with activation of NO in cardiomyocyte of normotensive and hypertensive rats.Item Populações de Hypsiboas albopunctatus (Anura, Hylidae) de ambientes urbanos e rurais diferem em relação às vocalizações, morfometria e aos tamanhos populacionais?(Universidade Federal de Goiás, 2009-09-28) Amaral, Ivan Borel; Bastos, Rogério Pereira; http://lattes.cnpq.br/6015137404238990In recent years, population declines of amphibians have been observed in different parts of the world. The process of fragmentation and destruction of habitats is considered the most threat to this diversity. Urbanization reduces species richness at assemblage of amphibian reproduction. Due to amphibians require a modest area for survival, some species can thrive in urban fragments. But small population sizes and isolation can cause the loss of genetic diversity and the extinction local. The advertisement calls are the most common vocalizations in anurans that primarily have the function to attract females and secondarily, serve to mediate aggressive interactions between males. For many species, individual reproductive success is directly proportional to the effort put in the corner. The variation between populations may be related to local adaptation, resource availability and reduced gene flow. This study aimed to test the following hypotheses: ( 1 ) Due to the effects of fragmentation and habitat destruction and urbanization , population sizes of Hypsiboas albopunctatus urban parks are smaller than the population size of rural populations , (2 ) There are differences morphometric H. albopunctatus between rural and urban environments , and ( 3 ) Due to the change of social structure as a function of fragmentation and influence of urban noise , there are differences in vocalizations of H. albopunctatus between rural and urban environments . The H. albopunctatus populations of urban and rural environments differ in population size , the body size and characteristics of the advertisement call. Urban populations were smaller than those of the rural environment. The results showed that populations are lower in smaller and changed urban fragments . Urban populations had a lower repetition rate of notes compared to rural environment . This fact may be related mainly to reduced population sizes and consequent behavioral change and structure of choirs of urban environments. It is unreasonable to reject the hypothesis that the sounds of car engines may influence the acoustic parameters of the corners of H. albopunctatus in urban environment. The population of H. albopunctatus Zoo vocalised in higher frequency bands and acoustic variable that is inversely related to body size of individuals as in other anurans. The population of this fragment was the one that differed from all others in both acoustic as morphometric characteristics. These results support the hypothesis that there are differences in the characteristics of the advertisement calls of Hypsiboas albopunctatus between rural and urban environments. The population of P. M. Jardim Botânico was the most distanced itself from the other urban populations in both acoustic and morphometric characteristics as the population size. This population was the most resembled the population characteristics of the rural environment. A same species of amphibian populations may have considerably differences in population structure, morphological and behavioral characteristics due to the fact that some are under the influence of the urban environment and other rural environment. The planning for the conservation of such populations requires more refined analysis that takes into account the aspects of ecological, behavioral and adaptive responses of this species in their specific environment.Item Efeitos metabólicos e reprodutivos da sobrenutrição pós-natal precoce em ratas Wistar provenientes da redução de ninhada durante a lactação: consequências na primeira e segunda geração(Universidade Federal de Goiás, 2019-04-17) Amaral, Keytiane de Jesus Viana; Cost, Renata Mazaro e; http://lattes.cnpq.br/5625298314637434; Gomes, Rodrigo Mello; http://lattes.cnpq.br/3121095341590269; Gomes, Rodrigo Mello; Costa, Renata Mazaro e; Corgosinho, Flávia Campos; Lima, Veridiana Mota MoreiraNutritional and environmental insults during perinatal period induces endocrine, functional and behavioral disorders in adulthood. Thus, it is necessary to assess the impact of infant feeding on the increased risk of obesity and other associated diseases, including in subsequent generations. The objective of the present study was to evaluate the metabolic and reproductive effects of early postnatal overnutrition in Wistar during lactation and the consequences in the second generation. Female Wistar rats (F0 generation) were distributed in two experimental groups: normal litter (NL, 9 pups, n=11) and reduced litter (SL, 3 pups, n=11) throughout the lactation period. On the 3rd postnatal day (PN3), litters SL were reduced to 3 pups/dam. After weaning (PN21), F1 females (NLF1 and SLF1) were fed with water and feed at will, and metabolic and reproductive parameters were analyzed in the adult (nulliparous), pregnancy and lactation phases. In the offspring of the F1 generation (F2 generation – GCF2 and GOF2), physical and sensory-motor, metabolic and reproductive parameters. In comparison to the NLF1 group, the SLF1 generation F1 group showed: a significant increase body weight in PN7, which was maintained during the adult phase, at the end of gestation and lactation; increased food intake during PN21 to PN70, without significant difference in the pregnancy and lactation phases; increase in the fat masses in the adult, pregnancy and lactation phases; increase in the masses of the liver in the lactation phase and of the pancreas in all phases; early of the onset of puberty and lower numbers of estrus; lower performance in sexual behavior; reduction in the number of corpus luteum, with no change in pre-implantation percentage, post-implantation losses and number of live male and female fetuses; fewer live births, both male and female; greater maternal care; reduction of serum estradiol concentration; increase in serum triglyceride concentrations and reduction of HDL cholesterol in pregnancy and lactation, with no change in total cholesterol levels; increase in adult glucose. In the histopathological analyzes there was also an increase in the area of adipocytes and the thickness of the adipose layer of the mammary glands; reduction in the number of growing follicles and increase in the number of cystic and atretic follicles in ovaries; endometrial glands with inflammatory cells and degenerating in the uterus. The GOF2 offspring, compared to the GCF2 offspring, presented higher body weight from birth to PN21, as well as higher milk intake in PN8. In the evaluation of the physical and sensory-motor development, the GOF2 offspring presented advance of the sensory-motor parameters (righting reflex, negative geotaxis, cliff avoidance) in males and females. However, the auditory startle reflex was later in males and females, with no significant difference in smell and free-fall righting parameters. Regarding the physical parameters, the eruption of the incisors was anticipated and the opening of the eyes delayed, without significant difference in the unfolding of the ears. The onset of puberty was anticipated in males and females. In conclusion, early postnatal overnutrition, acting as a factor of metabolic programming, promoted obesity, metabolic and reproductive changes in F1 generation rats and, consequently, also promoted metabolic and reproductive changes and in the physical and sensory-motor development of F2 offspring.Item Envolvimento do núcleo pré-óptico mediano (MnPO) na recuperação cardiovascular induzida pela infusão de salina hipertônica em animais submetidos ao choque hemorrágico(Universidade Federal de Goiás, 2014-04-16) Amaral, Nathalia Oda; Custodio, Carlos Henrique Xavier; Pedrino, Gustavo Rodrigues; http://lattes.cnpq.br/1155446449250341; Oliveira, André Henrique Freiria de; Ferreira Neto, Marcos Luiz; Ferreira, Patrícia Maria; Castro, Carlos Henrique deIn recent decades, several studies have demonstrated that hyperosmolarity induced by hypertonic saline infusion (HS) it’s a benefit for hypovolemic hemorrhage treatment. The median preoptic nucleus (MnPO) is known to receive information from central osmoreceptors and peripheral afferents about plasma osmolarity changes, reflexively modulating autonomic and neuroendocrine adjustments, primarily through its projections to the paraventricular nucleus (PVN). The present study aim to determine MnPO involvement in cardiovascular recovery induced by HSI in rats subjected to hemorrhagic shock (HC). Wistar rats (250 - 300 g) were prepared to record mean arterial pressure (MAP), heart rate (HR), renal blood flow (RBF) and aortic (ABF). The renal vascular conductance (RVC) and aortic (AVC) were calculated through the ratio between RBF and ABF with MAP, respectively. Hemorrhagic shock was induced by blood withdrawal over 10 min until the MAP reached approximate values of 60 mmHg. The sodium overload by infusion HS (3 M NaCl, 1.8 ml ∙ kg-1 body mass index) was made 2 min after the nanoinjection (100 nL) of GABA agonist muscimol (4 mM experimental group 1 - EXP 1 ), α-adrenergic antagonist phentolamine (13 mM ; experimental group 2 - EXP 2) or isotonic saline (NaCl, 0.15 M, control group - CON) in MnPO. This resulted in HC CON (n=6) MAP reduction (98.4 ± 5.3 to 62.2 ± 1.1 mmHg after 20 min HC, p<0.05), a decrease in RVC (- 59.4 ± 9.2%, 20 min after HC, p<0.05) and did not alter the AVC (-11.5 ± 10.5%, 20 min after HC) and HR (387.2 ± 12 to 351.7 ± 13 bpm after 20 min HC). HC promoted in EXP 1 (n=6) MAP reduction (98 ± 5.4 to 61 ± 0.7 mmHg after 20 min HC, p<0.05), a decrease in RVC (-64.8 ± 10.9%, 20 min after CH, p<0.05) and CVA (-32.3 ± 4.4%, 20 min after HC, p<0.05) and did not alter HR (389 ± 23.9 ± 17.1 to 360 bpm after 20 min HC). In EXP 2 (n=6) HC resulted in a MAP reduction (102.0 ± 4.2 to 62.0 ± 1.1 mmHg, 20 min after HC, p<0.05), a decrease in CVR (-27.6 ± 5.8% after 20 min HC, p <0.05), CVA (-4.5 ± 4.1% after 20 min HC, p<0.05) and HR (387 ± 14 to 347 ± 7.4 bpm after 20 min HC). HS infusion enabled MAP restoration (105.2 ± 3 mmHg, 60 min after infusion of HS, p<0.05), did not alter HR (400 ± 18.4 bpm, 60 min after infusion of HS) raised the RVC to baseline xi levels (-14.6 ± 14.2%, 60 min after infusion of HS, p<0.05) and reduced AVC (- 27.4 ± 4.3%, 60 min after infusion HS, p<0.05) in CON. HS infusion in EXP 1 was not able to restore MAP (54 ± 3.8 mmHg, 60 min after infusion of HS, p<0.05) and RVC (- 48.1 ± 9.7%, 60 min after infusion of HS, p<0.05), did not alter HR (361 ± 15.3 bpm, 60 min after infusion of HS) and was able to promote an increase in AVC similar to baseline (-23.2 ± 10.6%, 60 min after infusion HS, p<0.05) levels. In EXP 2, HS infusion enabled MAP restoration (89 ± 3.3 mmHg, 60 min after infusion of HS, p<0.05) but this return to baseline was delayed and occurred only 50 min after HS infusion (88 ± 3.3 mmHg), HR return (379 ± 6.5 bpm, 60 min after infusion of HS) and RVC to basal levels (-16.1 ± 8.9%, 60 min after infusion HS, p<0.05) and an increase in AVC 10 min after HS infusion (20.3 ± 6.4%, p<0.05), which was restored to levels similar to baseline at registration end (-15.7 ± 6.2%, 60 min after infusion of HS, p<0.05). Together, the results obtained in this study showed that MnPO plays an important role in cardiovascular recovery induced by HS infusion in HC cases. Furthermore, the cardiovascular adjustments involved in this resuscitation seem to depend partly on adrenergic neurotransmission in this nucleus.Item Dieta hiperlipídica e hipernatremia: alterações autonômicas e cardiovasculares(Universidade Federal de Goiás, 2018-02-02) Amaral, Nathalia Oda; Colombari, Débora Simões de Almeida; http://lattes.cnpq.br/1684467594359403; Pedrino, Gustavo Rodrigues; http://lattes.cnpq.br/1155446449250341; Pedrino, Gustavo Rodrigues; Oliveira, André Henrique Freiria; Gomes, Rodrigo Mello; Amaral, Vanessa Cristiane de Santana; Rebelo, Ana Cristina SilvaHypertension is the most common pathologies which affect population. Of the factors that can promote hypertension, food behavior is highlighted in relation to unhealthy eating habits present in western diet. Thus, present study sought to evaluate some aspects of this pathology in several situations, and themes were discussed separately in two chapters. In the first moment, effect of maternal hyperlipidic diet on metabolic and autonomic parameters in offspring was evaluated. It is known which obesity induced by maternal diet can modify central regulatory pathways of the fetus, mainly long-term regulation of appetite, but no work sought to evaluate the influence of the maternal hyperlipidic diet (HD) on cardiovascular and autonomic parameters in the offspring . Female Holtzman rats (280-300 g) were divided into two groups. One group received standard diet (SD) and other HD. The animals had free access to SD or HD for 6 weeks prior and during gestation and lactation period. All pups were weaned after 21 days of life and had free access to SD. After one week some offspring and mothers were submitted to glycemic test and later euthanized for removal of adipose tissue and blood. Other offspring were submitted to in situ preparation. DH increased adipose tissue in all females, but was able to change only metabolic triacylglycerols concentration. Offspring of HFD dams (OffHFD) showed an increase in adipose tissue and total cholesterol and HDL levels. Offspring of SD dams (OffSD) showed decrease in sympathetic activity after pre-colicular transection. This effect was not observed in males offspring of mothers with HFD (OffHFD). KCN infusion caused similar increases in abdominal activity (ABD), in phrenic nerve frequency (PNA f) and sympathetic activity (SNA), but in OffHFD this increase in SNA was smaller. KCN caused increase in phrenic nerve amplitude (PNA) and was higher in OffHFD. Hypercapnia resulted in increase in SNA, ABD and PNA and decrease in PNA f in both groups. The decrease in PNA f was more pronounced in OffHFD and increased PNA was higher in OffHFD. Phenylephrine caused in both groups decrease in SNA, ABD and PNA, and generated an increase in PNA f. The reduction of SNA was higher in OffHFD. These results suggest that maternal HFD during fetal development alters central connections in offspring. In second moment oxytocin effects on vascular reactivity and its role in hypernatremia-induced responses were evaluated. Changes in volume and/or extracellular compartments composition are known to evoke various autonomic, cardiovascular and hormonal responses that to modulate renal excretion of water and sodium. The main vegetative adjustments are: renal vasodilation and oxytocin secretion. Regulation of osmolarity and volume is critical for survival. Despite knowledge, no study evaluated interaction between renal sympathetic activity and oxytocin secretion on renal and cardiovascular responses induced by sodium overload. Male Wistar rats (280–350 g) were anesthetized with sodium thiopental (40 mg/kg, i.v.). Animals were also instrumented for measurement of mean arterial pressure (MAP) and renal blood flow (RBF). Renal vascular conductance (RVC) was calculated as the ratio of RBF by MAP. In anesthetized rats (n = 6), OT infusion (0.03 μg/kg, i.v.) induced renal vasodilation. Ex vivo experiments demonstrated that OT caused renal artery relaxation. Blockade of OT receptors (OTR) reduced these responses to OT, indicating a direct effect of this peptide on OTR on this artery. Hypertonic saline (3 M NaCl, 1.8 ml/kg b.wt., i.v.) was infused over 60 s. In sham rats (n=6), hypertonic saline induced renal vasodilation. The OXTR antagonist (AT; n=7) and renal denervation (RX) reduced the renal vasodilation induced by hypernatremia. Atosiban with renal denervation (RX+AT; n=7) completely abolished renal vasodilation induced by sodium overload. Intact rats excreted 51% of the injected sodium within 90 min. Natriuresis was slightly blunted by atosiban and renal denervation (42% and 42% of load, respectively), whereas atosiban with renal denervation reduced sodium excretion to 16% of the load. These results suggest that OT and renal nerves are involved in renal vasodilation and natriuresis induced by acute plasma hypernatremia. The understanding of regulatory mechanisms activated both during obesity and during hyperosmolarity allows greater possibility development new therapeutic tools for hypertension prevention and treatment.