Angiotensin II stimulates both aldosterone secretion and DNA synthesis viatype 1 but not type 2 receptors in bovine adrenocortical cells

Angiotensin II (Ang II) type 2 receptor (AT2) has been shown to counteract the type 1 receptor (AT1)-mediated biological actions of Ang II in the card iovascular system. The biological significance of AT2 receptor in the adren als however remains unknown. In the present study, we investigated the role s of AT1 and AT2 receptor subtypes in the regulation of aldosterone secreti on and DNA synthesis in bovine adrenocortical zona glomerulosa cells in vit ro. Ang II (1 mu mol/l)-stimulated aldosterone secretion was completely sup pressed by AT1 antagonist CV-11974 but not affected by AT2 receptor antagon ist PD-123319. Effects on DNA synthesis were investigated by determining th e incorporation of BrdU into the nuclei of the cultured zona glomerulosa ce lls. Ang II (1 mu mol/l)-stimulated DNA synthesis of the cells was also com pletely suppressed by CV-11974 but not by PD-123319. These results suggest that AT1 receptor but not AT2 receptor is the predominant receptor subtype which mediates the Ang II-stimulated aldosterone secretion and cell growth in bovine adrenocortical cells. (J. Endocrinol. Invest. 21: 668-672, 1998) (C)1998, Editrice Kurtis.