AJP - Renal Physiology, Vol 235, Issue 5 458-F464, Copyright © 1978 by American Physiological Society
Stimulation of adenylate cyclase in isolated rat glomeruli by prostaglandins
D. Schlondorff, P. Yoo and B. E. Alpert
The effect of prostaglandins and various agents on cyclic adenosine
3',5'-monophosphate generation was studied in isolated rat glomeruli.
Specific activity of adenylate cyclase in the glomeruli showed a 12-fold
increase over the crude homogenate and a fivefold increase over a tubular
preparation. Prostacyclin (PGI2) preferentially stimulated adenylate
cyclase of isolated glomeruli at a concentration as low as 10(-9) M.
Prostaglandins (PGE1, PGE2, and PGA2) and parathyroid hormone (1-34
synthetic PTH fragment) increased adenylate cyclase in glomeruli with
maximal stimulation at 2 X 10(-5) M and 2-4 microgram/ml, respectively. No
inhibition of PGE2 on PTH stimulation was observed. Isoproterenol (2 X
10(-4) M) caused a small stimulation, while PGF2alpha, arginine
vasopressin, and angiotensin II were ineffective. The presence of guanosine
triphosphate in the adenylate cyclase assay enhanced basal and PGE2- and
PTH-stimulated activity, but had no effect on NaF stimulation. These
findings show an effect of prostaglandins and PTH on the glomerular cAMP
system and raise the possibility of a physiological action of these agents
on the glomerulus.
