Effect of experimentally-induced hypertension on angiotensin converting enzyme activity in the aortic endothelium and smooth muscle cum adventitia of the Sprague Dawley rat.

The effect of experimentally-induced hypertension on the angiotensin converting enzyme (ACE) activity in the endothelium and smooth muscle cum adventitia of the Sprague Dawley rats was investigated. The ACE activity in both tissues of the 1-clip 2-kidney renovascular hypertensive rats and the deoxycorticosterone acetate/salt hypertensive rats were significantly higher than those of the normotensive control. These findings (i) support the suggestion that the 1-clip 2-kidney renovascular hypertensive rat represents a model of renin- and angiotensin-dependent hypertension and that the increased vascular ACE activity could play a role in the maintenance of hypertension (ii) provide new information regarding the association of increased vascular ACE activity and hypertension in the mineralocorticoid/salt treated hypertensive rats which may account for the finding by others that captopril is effective in preventing the development of hypertension in this low renin model of hypertension. On the other hand, the data also bring forth the possibility that the observed increase in vascular ACE activity could be the result of hypertension.