Angiotensin-II down-regulates cardiac natriuretic peptide receptor-A mediated anti-hypertrophic signaling in experimental rat hearts

Venkatachalam Gopi, Arumugam Parthasarathy, Subramanian Umadevi, Elangovan Vellaichamy
2013 Indian journal of experimental biology  
Atrial natriuretic peptide (ANP) exerts anti-hypertrophic effects in the heart via natriuretic peptide receptor-A (NPR-A). However, ANP mediated anti-hypertrophic activity is decreased in the cardiomyopathic conditions. In the present investigation the in vivo effects of angiotensin II (Ang II), a hypertrophic agonist have been studied on the ventricular expression level of NPR-A in Wistar rat hearts. NPR-A expression at the protein and mRNA levels were found to be markedly reduced by 5-fold
more » ... pectively in Ang II infused rats heart as compared with sham rat hearts. Moreover, cGMP production in response to ANP was reduced by 77% in the isolated cardiac membrane preparation from the Ang II infused rat hearts. Losartan treatment reversed NPR-A expression and responsiveness to ANP. This study suggests that Ang II down regulates cardiac NPR-A activity by suppressing Npr1 gene transcription.
pmid:23441479 fatcat:qiqmc5ybonbrhn2b3nrevcb5le