Potential apoptotic role of Angiotensin II type 2 receptors in rat kidney development.

SÁNCHEZ S, SANCHEZ L, FORNERIS M, CIUFFO G.

San Luis

Congreso; Soc. Biología de Cuyo; 2009

Soc. de Biologia de Cuyo

Evidence suggests that Angiotensin II (Ang II) plays an important role in the complex process of renal organogenesis. Ang II binds and activates two major receptor subtypes, namely AT1 and AT2.  Previously, we demonstrated that PD123319-treated animals exhibited kidneys with an enlarged nephrogenic zone and increased number of immature glomeruli. Since a pro-apoptotic role has been attributed to AT2 receptors, the aim of present study was to examine the role of apoptosis mediated by AT2 receptors in kidney development. We studied two groups at postnatal days 0, 8 and 15 (P0, P8, P15), control animals and those born from mothers treated with AT2 antagonist (PD123319, 1mg/kg/day) during late pregnancy. In this study we detected the expression of AT2 receptors, the pro- and anti-apoptotic genes, Bax and Bcl2 by RT-PCR. In control animals, Bax expression was higher at P8 and decreased by P15 while Bcl2 expression was low and almost constant at all ages. For PD123319-treated animals, lower levels were observed for both Bax and Bcl2 genes at all stages. DNA fragmentation was diminished in animals treated with PD123319. Recently, a potential role has been attributed to Bcl2 in cell adhesion mechanisms during kidney development. Taken together, these data suggest that Ang II AT2 receptors could module the Bcl-2 expression required for the proper maturation of the kidney.