Plasma endothelin-1 level in patients with renovascular hypertension - does the kidney with stenosis of the renal artery upregulate production of endthelin-1?
OBJECTIVE
To examine the value of plasma endothelin-1 (ET-1), we measured the level of plasma ET-1 activity of peripheral venous blood and selective renal venous blood in renovascular hypertension patients, and compared that activity with corresponding renin activity and split renal function.


METHODS
ET-1 level, renin activity in selective renal venous blood and peripheral venous blood, and 99mTc-dimercaptosuccinic acid renal uptake as a split renal function test were measured in 11 patients (mean 42.1 years old) with renovascular hypertension (RVH) and 6 patients with both renal cell cancer (RCC) and essential hypertension.


RESULTS
1. In patients with RVH, resting peripheral venous plasma ET-1 ranged from 0.6 to 8.1 (mean 4.07) pg/ml and was higher than the normal level (p <0.01). However, the renal vein ET-1 ratio was nor correlated with the renal vein renin ratio. 2. In patients with RCC, resting peripheral venous plasma ET-1 was not different from the normal level. There was no step-up of plasma ET-1, or renin among renal veins, or the proximal and distal parts of the interior vena cava. 3. Both renal vein renin ratio and renal vein ET-1 ratios were inversely correlated with t99mTC-dimercaptosuccinic acid renal uptake as a split renal function examination in patients with RVH. 4. The peripheral plasma ET-1 level was correlated with the degree of stenosis of the renal artery in patients with RVH of a unilateral lesion, but not bilateral lesions.


CONCLUSIONS
These results suggest that ET-1 may take part in the hypertensive mechanisms of RVH in addition to the renin-angiotensin system, but its significance in RVH still remains to be examined.
Takeda
M
M
Department of Urology, Niigata University School of Medicine, Asahimachi, 1 Niigata 951, Japan. takedama@med.niigata-u.ac.jp
Saito
K
K
Tsutsui
T
T
Mizusawa
T
T
Obara
K
K
Tomita
Y
Y
Takahashi
K
K
D000293:Adolescent; D000328:Adult; D000368:Aged; D000959:Antihypertensive Agents; D002216:Captopril; D002675:Child, Preschool; D019332:Endothelin-1 / Q000096:biosynthesis / Q000097:blood*; D005260:Female; D006801:Humans; D006978:Hypertension, Renovascular / Q000097:blood* / Q000000981:diagnostic imaging; D007668:Kidney / Q000187:drug effects / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015609:Organotechnetium Compounds; D011863:Radioimmunoassay; D011877:Radionuclide Imaging; D012077:Renal Artery / Q000503:physiopathology; D012083:Renin / Q000097:blood; D004113:Succimer; D019783:Technetium Tc 99m Dimercaptosuccinic Acid
D000959:Antihypertensive Agents; D019332:Endothelin-1; D015609:Organotechnetium Compounds; D019783:Technetium Tc 99m Dimercaptosuccinic Acid; D002216:Captopril; D004113:Succimer; D012083:Renin