title: Prostaglandin independence of kinin-stimulated renin release.
abstract: Bradykinin can increase prostaglandin synthesis and also stimulate renin release in vitro. Because prostaglandins also stimulate renin, studies were performed to determine whether bradykinin stimulation of renin is a function of prostaglandin synthesis. Isolated glomeruli with attendant arteriolar attachments were harvested from rat kidneys and superfused. The effluent was analyzed for renin, prostaglandins E2 and I2 (6-keto-PGF1 alpha). Bradykinin (10(-5) M) increased renin by 50% with a concomitant increase in prostacyclin (PGI2) but not in prostaglandin E2 (PGE2). The cyclooxygenase inhibitor meclofenamate (1.6 X 10(-5) M) inhibited bradykinin-induced PGI2 synthesis but not the concurrent increase in renin release. Additionally, neither the phospholipase inhibitor quinacrine (10(-2) M) nor the prostacyclin synthetase inhibitor 9,11-azoprosta-5,13-dienoic acid (Azo analogue-1) (5.67 X 10(-6) M) eliminated bradykinin-induced renin release. Superfusion with calcium-free media and EDTA increased basal renin release 2.5-fold, and bradykinin stimulated a twofold increase in renin release. Neither a high (10(-2) M) media calcium nor the calcium channel blocker nifedipine (10(-6) M) eliminated bradykinin stimulation of renin. These results suggest that bradykinin stimulation of renin is at least partially independent of prostaglandin synthesis and that bradykinin must act by some prostaglandin-independent pathway to induce renin release from isolated glomeruli.
mesh_terms: D000818:Animals; D001920:Bradykinin / Q000494:pharmacology*; D002118:Calcium / Q000502:physiology; D066298:In Vitro Techniques; D007678:Kidney Glomerulus / Q000378:metabolism; D008297:Male; D011448:Prostaglandin Antagonists / Q000494:pharmacology; D011453:Prostaglandins / Q000096:biosynthesis*; D051381:Rats; D011919:Rats, Inbred Strains; D012083:Renin / Q000378:metabolism*
chemical_list: D011448:Prostaglandin Antagonists; D011453:Prostaglandins; D012083:Renin; D001920:Bradykinin; D002118:Calcium