Angiotensin-II down-regulates cardiac natriuretic peptide receptor-A mediated anti-hypertrophic signaling in experimental rat hearts.
نویسندگان
چکیده
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 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.
منابع مشابه
Genetic disruption of guanylyl cyclase/natriuretic peptide receptor-A upregulates ACE and AT1 receptor gene expression and signaling: role in cardiac hypertrophy.
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عنوان ژورنال:
- Indian journal of experimental biology
دوره 51 1 شماره
صفحات -
تاریخ انتشار 2013