Comparison of intrarenal and extrarenal converting-enzyme inhibition by SQ 20 881 on canine renal blood flow.
1. Successive infusions of SQ 20 881 given intra-arterially (i.a.) to the kidney at 0.4 and 0.8 microgram min-1 kg-1 for 50 min each did not alter renal blood flow and renal vascular resistance in spite of 40--47% blockade of the angiotensin I (ANG I i.a.)-induced vasoconstrictor response. 2. SQ 20 881 administered intravenously (i.v., 0.5 mg/kg) after the higher intra-arterial dose did not further decrease the renal response to ANG I (i.a.), but caused an increase in renal blood flow and a decrease in renal vascular resistance. 3. These results indicate that SQ 20 881 has limited efficacy in blocking the renal response to ANG I (i.a.). Under the conditions of these experiments, the renal vasodilator response to SQ 20 881 appears to be due to inhibition of extrarenal rather than intrarenal converting enzyme.
D000803:Angiotensin I / Q000378:metabolism; D000804:Angiotensin II / Q000378:metabolism; D000806:Angiotensin-Converting Enzyme Inhibitors; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D004285:Dogs; D005260:Female; D007269:Injections, Intra-Arterial; D007275:Injections, Intravenous; D007668:Kidney / Q000201:enzymology*; D008297:Male; D009842:Oligopeptides / Q000494:pharmacology*; D012079:Renal Circulation / Q000187:drug effects*; D013722:Teprotide / Q000008:administration & dosage / Q000494:pharmacology*; D014664:Vasodilation / Q000187:drug effects
D000806:Angiotensin-Converting Enzyme Inhibitors; D009842:Oligopeptides; D000804:Angiotensin II; D000803:Angiotensin I; D013722:Teprotide