AJP - Regulatory, Integrative and Comparative Physiology, Vol 264, Issue 2 402-R408, Copyright © 1993 by American Physiological Society
Is arterial pressure a determinant of renal prostaglandin release?
H. Ehmke, P. B. Persson, E. Hackenthal, H. Schweer, H. W. Seyberth and H. R. Kirchheim
I. Physiologisches and Pharmakologisches Institut, Universitat Heidelberg, Germany.
The effect of changes in renal perfusion pressure (RPP) on renal
prostaglandin (PG) release was investigated in conscious dogs (n = 10).
PGE2, PGF2 alpha, and 6-keto-PGF1 alpha levels in renal venous and aortic
plasma were measured in response to controlled reductions of RPP by an
inflatable cuff implanted around the renal artery. PG plasma concentrations
were determined by gas chromatography-negative ion chemical ionization mass
spectrometry. At control RPP, PGE2 and PGF2 alpha concentrations in renal
venous plasma were severalfold higher than in aortic plasma (PGE2, 54.2 +/-
13.4 vs. 9.3 +/- 2.7 pg/ml, P < 0.01; PGF2 alpha, 40.3 +/- 10.4 vs. 10.4
+/- 3.4 pg/ml, P < 0.01), whereas only a small secretion rate was found
for 6-keto-PGF1 alpha (renal vein, 24.3 +/- 2.6 pg/ml; aorta, 17.4 +/- 3.4
pg/ml; P < 0.01). Concentrations of all three PGs in renal venous or
aortic plasma did not change in response to reductions of RPP within the
normal range of renal blood flow (RBF) autoregulation. The mean difference
between PG release at a RPP of 70 mmHg and control was for PGE2 -7.9 pg/ml
with a 95% confidence interval (CI) from -20.7 to + 5.0 pg/ml; for PGF2
alpha it was -13.7 pg/ml (95% CI -29.4 to +2.0 pg/ml); and for 6-keto-PGF1
alpha it was -0.9 pg/ml (95% CI -6.0 to +4.1 pg/ml). Reductions of RPP
below the lower limit of RBF autoregulation (< 66 mmHg) had no effect on
6-keto-PGF1 alpha secretion rate but decreased secretion rates of PGE2 and
PGF2 alpha (n = 4).(ABSTRACT TRUNCATED AT 250 WORDS)
