Effect of PGE2 on the cell cyclic AMP content in the thin descending limb of Henle of the rat.
Effects of prostaglandins (PG) on intracellular cAMP content were examined in an intact cell preparation of single nephron segments dissected from rat kidney. PGE2 markedly increased cell cAMP in the thin descending limb of Henle (tDL) in a dose-dependent manner. Significant increases in cell cAMP were observed at 1-10 ng/ml PGE2, concentrations prevailing in the renal medulla in vivo, and the increase reached a maximum at a PGE2 concentration of 10 micrograms/ml. PGI2 also increased cell cAMP in the tDL, but the doses required were two orders of magnitude higher than those for PGE2. PGF2 alpha had only a minor effect, if any. PGE2 but not PGI2 also increased cell cAMP of rabbit tDL, but to a lesser magnitude than that seen in the rat tDL. PGE2 increase cell cAMP slightly in the cortical-collecting tubules at 10 micrograms/ml but no significant effect was seen in other nephron segments tested including proximal convoluted tubules, cortical and medullary thick ascending limbs of Henle, and medullary-collecting tubules. Results suggest a possible physiological effect of PGE2 via cAMP on the tDL thereby affecting the function of the renal medulla. Such an effect of PGE2 may underlie, at least in part, in the inhibition by PGE2 of vasopressin-mediated urinary concentration.
D000818:Animals; D000242:Cyclic AMP / Q000032:analysis*; D015237:Dinoprost; D015232:Dinoprostone; D004305:Dose-Response Relationship, Drug; D011464:Epoprostenol / Q000494:pharmacology; D007684:Kidney Tubules / Q000187:drug effects*; D008138:Loop of Henle / Q000032:analysis / Q000187:drug effects*; D008297:Male; D009399:Nephrons / Q000187:drug effects; D011458:Prostaglandins E / Q000494:pharmacology*; D011460:Prostaglandins F / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
D011458:Prostaglandins E; D011460:Prostaglandins F; D015237:Dinoprost; D011464:Epoprostenol; D000242:Cyclic AMP; D015232:Dinoprostone