Contraction and Relaxation Responses of Contralateral Renal Artery in Renovascular Hypertension

Choi, Seung Ok; Yoon, Young Wook; Lee, Moo Yeol; Nahm, Sook Hyun

Abstract

Experimental renovascular hypertensive model was established by clipping left renal artery and the right side of renal artery was taken 1 week and 1 month after the operation. The renal artery ring preparations were made for contractility studies of vascular wall. The relaxing and contractile responses were recorded and compared with the data obtained from control group. The following results were obtained: 1)One week after the clipping of renal artery, the renovascular hypertensive group showed increased contractility against the various contractile agents (high K+, norepinephrine, caffeine) compared to control group. 2)One month after the clipping of renal artery, the contractile responses to various contractile agents were restored to the level of control group. 3)One week after the clipping of renal artery, the renovascular hypertensive group showed increased responsiveness to acetylcholine treatment, however did not show any remarkable changes to other relaxing agents(sodium nitroprusside, verapamil). 4)One month after the clipping of renal artery, the responses to various relaxing agents showed almost same degree of responsiveness in the renovascular hypertensive group as compared with that of control group. From the above, it is suggested that stenosis- induced renovascular hypertension might induce exaggerated vascular response at early stage in intact renal artery. And the effects may be concerned with endothelium-dependent mechanism.