Expression of angiotensin-converting enzyme in renovascular hypertensive rat kidney.
We hypothesized that the gene expression of angiotensinogen, angiotensin-converting enzyme, and angiotensin II type 1 receptor, in addition to renin, is increased in kidneys after renal artery stenosis. Two-kidney, one clip renovascular hypertension was initiated in Sprague-Dawley rats by clipping of the left renal artery; control rats were sham operated. Blood pressure was not changed for the first 2 days after clipping but was elevated on day 4 (mean arterial pressure, 104 +/- 4 versus 87 +/- 2 mm Hg in sham-operated control rats, P < .002) and increased further during the next 24 days. Rats were killed 2, 4, 7, 14, and 28 days after clipping or sham operation, and poly(A)(+)-purified renal cortical RNA was analyzed by Northern blotting. Autoradiographs were quantitated by densitometry and normalized for the expression of a housekeeping gene. Renin expression was increased in the clipped kidney (by 149% on day 2) and decreased in the nonclipped kidney (by 82% on day 2), compared with kidneys of control rats. Expression of the angiotensin-converting enzyme was increased in clipped kidneys from the first day after clipping (158%) and throughout the experiment (66% on day 28), but was unchanged or slightly decreased in nonclipped kidneys. Angiotensinogen mRNA showed little change. Angiotensin II type 1 receptor expression was decreased in nonclipped kidneys but unchanged during the first 7 days in clipped kidneys. Our results show that components of the renin-angiotensin system other than renin are also differentially expressed in clipped kidneys.(ABSTRACT TRUNCATED AT 250 WORDS)
Mai
M
M
Department of Medicine IV, University of Erlangen, Berlin-Buch, Germany.
Hilgers
K F
KF
Wagner
J
J
Mann
J F
JF
Geiger
H
H
D000804:Angiotensin II / Q000097:blood; D000808:Angiotensinogen / Q000235:genetics; D000818:Animals; D006978:Hypertension, Renovascular / Q000378:metabolism*; D007668:Kidney / Q000201:enzymology*; D008297:Male; D007703:Peptidyl-Dipeptidase A / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011945:Receptors, Angiotensin / Q000235:genetics; D012083:Renin / Q000097:blood
D012333:RNA, Messenger; D011945:Receptors, Angiotensin; D000808:Angiotensinogen; D000804:Angiotensin II; D007703:Peptidyl-Dipeptidase A; D012083:Renin