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

作者：Gopi Venkatachalam; Parthasarathy Arumugam; Umadevi Subramanian; Vellaichamy Elangovan^*

来源：Indian Journal of Experimental Biology, 2013, 51(1): 48-55.

• Angiotensin-II
• Atrial natriuretic peptide
• Guanylyl cyclase activity
• Left ventricular hypertrophy
• Natriuretic peptide receptor-A

Atrial natriuretic peptide (ANP) exerts and-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 respectively 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.

• 出版日期2013-1