Prostaglandin synthesis by isolated rat renal glomeruli.

The PGE2, PGF2 alpha and 6-keto-PGF1 alpha contents of the incubation medium of glomeruli isolated from rat kidney were measured at different times with or without addition of arachidonic acid. These prostaglandins accumulated progressively with time and reached equilibrium after 60--120 min incubation. Synthesis of the 3 prostaglandins was inhibited when indomethacin was added whereas it was markedly enhanced, mainly for PGE2, at increasing doses of arachidonic acid. Plateaus were reached above 5 micrograms/ml and concentrations corresponding to 50% of the maximum values were 2 micrograms/ml for PGE2 and PGF2 alpha, and 0.8 microgram/ml for 6-keto-PGF1 alpha. There were strictly linear relationships between PGE2 or PGF2 alpha productions and the concentration of glomerular protein. PGE2 and PGF2 alpha synthesis with or without arachidonic acid were maximum at 30--37 degrees C. PGE2 glomerular content was almost undetectable initially and increased with time. These data demonstrate that PGE2, PGF2 alpha and PGI2, in order of decreasing abundance, are synthesized by the glomerular cells and suggest that PGE2 and PGI2-sensitive glomerular adenylate cyclase activities and PGE2-sensitive renin synthesis may be stimulated by prostaglandins formed in the glomeruli themselves.