AJP - Renal Physiology, Vol 250, Issue 5 811-F816, Copyright © 1986 by American Physiological Society
Synergistic action of angiotensin II on norepinephrine-induced prostaglandin release from rat glomeruli
Y. Matsumura, Y. Ozawa, H. Suzuki and T. Saruta
The effects of vasoactive substances on the release of prostaglandin (PG)
and thromboxane (TX) from isolated rat glomeruli were investigated. The
PGE2, PGF2 alpha, 6-keto-PGF1 alpha, and TXB2 release during 60 min into
Krebs-Henseleit medium was assessed by radioimmunoassay following
extraction. Norepinephrine (NE) stimulated PGE2 (from 2,117 +/- 117 to
3,968 +/- 182 pg X mg protein-1 X 60 min-1, P less than 0.01) at a
concentration of 10(-4)M and PGF2 alpha (from 2,748 +/- 285 to 8,535 +/-
495 pg X mg protein-1 X 60 min-1, P less than 0.01) at a concentration of
10(-5)M. However, neither angiotensin II (ANG II) nor arginine vasopressin
(AVP) affected the release of PG and TXB2 at concentrations up to 10(-5)M.
In the presence of 10(-5) M NE, ANG II enhanced the release of PGE2 (from
3,307 +/- 207 to 6,865 +/- 469 pg X mg protein-1 X 60 min-1., P less than
0.01) and PGF2 alpha (from 3,652 +/- 252 to 6,612 +/- 388 pg X mg protein-1
X 60 min-1, P less than 0.01) at a concentration of 10(-8)M, whereas AVP
lacked any similar effect. These results indicate that catecholamine acts
as a major stimulant for the release of PG from isolated glomeruli via
alpha-receptors. ANG II may work in cooperation with catecholamine, but AVP
appears to play little role.
