Role of angiotensin type 2 receptor on nitric oxide production response to angiotensin II administration in ovariectomised rats treated with estradiol

ABSTRACT

Renin-angiotensin system activity is gender related. The vasodilatory response of angiotensin II [AngII] angiotensin type 2 receptor [AT2R] may involve nitric oxide [NO] production. We attempted to find the role of AT2R on NO formation response to AngII administration in ovariectomised rats treated with estradiol [OVE]. A total of 33 female Wistar rats were divided into 3 groups; intact animals, ovariectomised treated with placebo [OVX] and OVE. At 2 weeks later, all animals were subjected to anesthetize and catheterize and each group was divided into two subgroups that received AT2R antagonist [PD123319] or vehicle. Each animal was subjected to 1 h continuous infusion of AngII [20 miceog/kg/h] and the level of NO metabolite [nitrite] was measured before and after AngII infusion. At the presence of AT2R, the serum level of nitrite in response to AngII administration in OVE groups increased significantly [P < 0.05]. However, this increase was abolished by AT2R antagonist. It seems that AT2R involves nitrite production response to AngII in OVE