AJP - Endocrinology and Metabolism, Vol 254, Issue 6 E687-E693, Copyright © 1988 by American Physiological Society
In vitro renal eicosanoid production during pregnancy in rabbits
G. P. Brown and R. C. Venuto
University of New York, Buffalo 14214.
The low renal resistance to blood flow in the presence of an activated
endogenous renin-angiotensin system in gravid animals may in part be
mediated by the action of eicosanoids produced in situ. To evaluate
intrarenal eicosanoid production during gestation in rabbits, we
quantitated immunoreactive PGE2, 6-keto-PGF1 alpha (a stable metabolite of
PGI2) and thromboxane B2 (a stable metabolite of thromboxane A2) in
unextracted media after incubation of renal slices and isolated glomeruli.
In cortical slices from nonpregnant and pregnant rabbits, PGE2 production
(micrograms.g-1.30 min-1) was 0.04 +/- 0.005 and 0.08 +/- 0.01 (P less than
0.01) and 6 keto-PGF1 alpha was 0.03 +/- 0.01 and 0.06 +/- 0.01 (P less
than 0.05), respectively. In papillary slices, PGE2 production was 14 +/- 2
and 21 +/- 2 (P less than 0.05) and 6 keto-PGF1 alpha was 4 +/- 1 and 5 +/-
1 (P greater than 0.05) for nonpregnant and pregnant rabbits, respectively.
Thromboxane B2 production was unchanged during pregnancy in both cortex and
papilla. Acute captopril administration to nonpregnant and to pregnant
rabbits in vivo failed to alter in vitro renal slice eicosanoid production.
Isolated glomeruli from nonpregnant and pregnant rabbits synthesized PGE2
at similar rates. Exogenous arachidonic acid increased PGE2 production (P
less than 0.05), but angiotensin II had no effect on eicosanoid production
in vitro. These data suggest that the net synthesis of vasodilator
eicosanoids is enhanced during gestation in rabbits.(ABSTRACT TRUNCATED AT
250 WORDS)
