Angiotensin Receptor Antagonists and Cardiovascular Remodeling

Angiotensin (Ang) II is one of the key hormones involved in cardiovascular homeostasis. It has potent vasoconstrictor effects and is directly involved in the vascular and cardiac remodeling observed in response to chronic or acute hypertension. Two major Ang II receptor subtypes, AT1 and AT2, have been described, and their roles in vivo and in vitro have now been investigated using nonpeptidic antagonists, losartan and PD123319, which block AT1 and AT2 receptors respectively. The aim of this review is to focus on in vivo data to better define the respective functions of the AT1 and AT2 receptor subtypes. In adult rats, the AT1 receptor subtype does not trigger trophic effects directly in cardiomyocytes, whereas the AT2 receptor may have a major trophic role in smooth muscle cells.