Analysis of the vasorelaxant action of angiotensin II in the isolated rat renal artery.

摘要: Taking into consideration that mechanisms involved in the vasodilatator actions of angiotensin II have not yet been completely elucidated, present study was undertaken order to examine underlying II-induced relaxation rat renal artery (RRA). Angiotensin produced concentration-dependent and endothelium-independent isolated RRA. partially reduced by inhibitors nitric oxide synthase guanylyl cyclase. The remaining dilatation inhibited a potassium channel blocker, charybdotoxin. Precontraction RRA with high concentration K(+) II-evoked relaxation, while indomethacin, glibenclamide, apamin barium did alter concentration-response curve. Losartan had no effect on effect. Oppositely, HOE 140 PD123319, separately or combination, antagonized vasorelaxation induced II. Complete blockade response obtained after simultaneous incubation all three receptor antagonists HOE-140, losartan; L-NOARG plus HOE-140; PD123319 These results indicate produces RRA, which is most probably mediated interaction NO-cGMP pathway channels. Moreover, we can assume AT(1), AT(2), B(2) receptors are vasorelaxant