AJP - Renal Physiology, Vol 259, Issue 4 660-F665, Copyright © 1990 by American Physiological Society
Recruitment of renin gene-expressing cells in adult rat kidneys
R. A. Gomez, R. L. Chevalier, A. D. Everett, J. P. Elwood, M. J. Peach, K. R. Lynch and R. M. Carey
Department of Pediatrics, University of Virginia School of Medicine, Charlottesville 22908.
To define whether angiotensin I-converting enzyme (ACE) inhibition affects
the distribution of renin gene-expressing cells within the kidney, a
control group of adult male Wistar-Kyoto rats (C, n = 7) was compared with
a group of rats treated with enalapril (E, n = 6) for 5 days. Renin mRNA
distribution was assessed using in situ hybridization to a 35S-labeled 28
mer oligonucleotide complementary to rat renin mRNA. Whereas in control
rats renin mRNA was confined to a juxtaglomerular location, in
enalapril-treated rats, renin mRNA extended proximally along the length of
the afferent arteriole. The percent of visible afferent arteriolar length
containing renin mRNA was higher in enalapril-treated (71.7 +/- 2.8%) than
in control (49.6 +/- 2.1%) rats (P less than 0.0001). These findings were
accompanied by an increase in the percent of juxtaglomerular apparatuses
(JGAs) containing renin mRNA (71 +/- 2.2 vs. 49 +/- 2.9%; E vs. C, P less
than 0.0001). Also, the intensity of the JGA hybridization signals was
higher in enalapril-treated (757 +/- 59 grains/JGA) than in control (167
+/- 11 grains/JGA) rats (P less than 0.00001). We conclude that the
increased kidney renin gene expression elicited by ACE inhibition is the
result of an increase in renin mRNA content per JGA, an increase in the
number of JGAs expressing the renin gene, and a recruitment of renin
gene-expressing cells along the afferent arteriole.
