Angiotensin II and norepinephrine after indomethacin in isolated perfused canine kidneys. Tachyphylaxis vs. modulator effect of prostaglandins.
High levels of radioimmunoassayable PGE2 were measured in the perfusate of isolated kidneys. Indomethacin inhibited PGE2 release in this system. Small reductions in the pressor effects of norepinephrine (NE) were associated with increasing perfusate levels of PGE2; a large increase in the pressor effect of NE followed additions of indomethacin and reductions in perfusate PGE2 levels. A marked reduction in pressor responsiveness to angiotensin II (AII) was measured in the isolated kidney which could not be prevented or reversed by indomethacin. It is believed that tachyphylaxis was responsible for the marked reduction in pressor responsiveness to AII and that this is independent of alterations in prostaglandin metabolism. However prostaglandins appeared to modulate the pressor effects of AII as they did NE in the isolated perfused kidney.
D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D004285:Dogs; D004357:Drug Synergism; D007213:Indomethacin / Q000494:pharmacology*; D007668:Kidney / Q000098:blood supply / Q000187:drug effects*; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology*; D010477:Perfusion; D011458:Prostaglandins E / Q000097:blood; D012039:Regional Blood Flow; D012083:Renin / Q000097:blood
D011458:Prostaglandins E; D000804:Angiotensin II; D012083:Renin; D009638:Norepinephrine; D007213:Indomethacin