“…In models unassociated with the administration of pressor agents, such as two kidney one-clip hypertension, there was no increase in pressor responsiveness to infused AngII. 15 Further, the administration of other pressor agents, such as ACTH, cyclosporin A and vasopressin, is associated with either no change in pressor sensitivity'6 or a decrease in pressor ~ensitivity.1~2'8 Thus, it is possible that this represents a direct effect of NO, whereby locally produced N O acts to decrease AngII receptor expression. Treatment with L-NAME, by decreasing NO production, may therefore prevent receptor down-regulation.…”