Comparison of renal vein renin activity in hypertensive patients with stenosis of one or both renal arteries.

Renal vein renin measurements were compared in 64 hypertensive patients with arteriographically documented stenoses or complete occlusion of one or both renal arteries. The characteristic pattern of curable renovascular hypertension, i.e. increased increment of renin from the ischaemic kidney with contralateral suppression of renin secretion, was seen not only in patients with unilateral stenoses, but also in most patients with bilateral stenoses. Contralateral suppression was less marked in azotemic patients. The highest increments of renal vein renin were seen when the renal artery was completely occluded. The patterns were similar following acute or chronic administration of captopril, suggesting that angiotensin II is not responsible. Increased sodium delivery to the macula densa is postulated as a possible cause of contralateral suppression.