[Angiotensin II type 2 receptor gene deletion does not affect renin-angiotensin system]

It has been postulated that Angiotensin II type 2 receptor (AT2) functionally antagonizes type 1 (AT1) receptor. In the present study, we investigated whether gene deletion of AT2 receptor causes the compensatory chaos of renin-angiotensin system in mice. It was shown that the concentrations of Angiotensin II in plasma and kidney tissues and the expressions of renin and AT1A receptor in the AT2 gene null mice were unchanged, as compared with those in AT2 wild-type mice. This result suggests that gene deletion of AT2 receptor does not markedly impact the stability of renin-angiotensin system and the inductive function of AT2 receptor is compensated in a way remaining to be clarified.