Receptor Mas contribui para o desenvolvimento do remodelamento cardíaco
Nenhuma Miniatura disponível
Data
2016-03-21
Autores
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Federal de Goiás
Resumo
Previous studies have demonstrated a protective effect of the Ang-(1-7)/Mas receptor
axis on pathological cardiac hypertrophy. Also, the involvement of Mas receptor in the
exercise-induced cardiac hypertrophy has been suggested. However, the role of the
Ang-(1-7)/Mas receptor on pregnancy-induced cardiac remodeling remains unknown.
Thus, the aim of this study was to evaluate the participation of the Mas receptor in the
development of pregnancy and hypertrophy, fibrosis and cardiac function during
pregnancy. Female Wistar rats were randomly shared in 3 groups: control (W-NP),
pregnant (W-P), and pregnant treated with A-779 (W-P + A-779). Wild type and Masknockout
mice were distributed in non-pregnant (WT and KO) and pregnant (WT-P and
KO-P) groups. Gestational parameters such as, maternal weight, placental weight, fetus
weight, fetus/placenta ratio, fertility, Loss pre embryonic, Loss pos embryonic were
evaluated. Systolic blood pressure (SBP) was measured by tail-cuff plethysmography.
The medial part of the left ventricle (LV) was collected for cardiomyocytes morphometry
analysis and extracellular matrix proteins deposition. Echocardiographic analysis was
used to evaluate the cardiac function. Mas receptor blockade or genetic deletion of Mas
did not alter the fertility or embryonic and fetal development. However, the Mas receptor
antagonist decreased placental weight and increased fetus placenta ratio in rats. The
pregnant KO mice presented a decreased maternal and fetal weight and increased
fetus/placenta ratio. SBP was not changed by pregnancy or A-779 treatment in the
Wistar rats. Pharmacological blockade or genetic deletion of Mas receptor attenuates
the pregnancy-induced myocyte hypertrophy. The A-779 treatment or genetic deletion
of the Mas receptor increased the collagen III deposition in LV from pregnant animals.
KO mice presented a lower ejection fraction, fraction shortening, stroke volume and
higher end systolic volume compared to WT. Interestingly, the pregnancy restored these
parameters. In conclusion, these data show that Mas receptor can alter gestational and
maternal parameters, and this is involved in the cardiomyocyte hypertrophy and in the
control of the collagen III deposition in pregnancy condition. These alterations are
associated with improvement of the cardiac function through Mas-independent
mechanism.
Descrição
Palavras-chave
Citação
SILVA, C.C. Receptor Mas contribui para o desenvolvimento do remodelamento cardíaco. 2016. 57 f. Dissertação (Meestrado em Biologia) - Universidade Federal de Goiás, Goiânia, 2016.