A possible role for leukotrienes in the regulation of glomerular haemodynamics in the dog.
In anaesthetized beagles, saralasin, phentolamine, 1-penicillamine-2-O-methyl-tyrosine-8-arginine-vasopressin and SCH 23390, a DA1 antagonist, were infused into the left renal artery (i.r.a.) and indomethacin and aprotinin intravenously (Group 1). In Groups 2 and 3, i.r.a. infusion of two chemically different putative leukotriene (LT) antagonists, FPL 55712 (100 micrograms/kg/min) and LY 171883 (500 micrograms/kg/min), respectively, was superimposed in the fourth period of experiments. In comparison to Group 1, there was an increase (40% in Group 2 and 33% in Group 3) in renal blood flow and a decrease in glomerular filtration rate (16% and 17%, respectively) and filtration fraction (36% and 41%, respectively). Similar changes were observed on the single nephron level. Directly measured glomerular capillary pressure decreased by 10% and 12%, respectively. A decrease in total arteriolar resistance by 34% and 25%, respectively, was caused by a comparatively higher decrease in efferent (44% and 34%, respectively) than afferent (26% and 15%, respectively) arteriolar resistance values. No change in the ultrafiltration coefficient, Kf, was detected. Providing FPL 55712 and LY 171883 are specific LT antagonists, these experiments suggest a possible constrictory role of LT (expressed more on the efferent than afferent arteriole) in anaesthetised mildly surgically stressed dogs.
Heller
J
J
Institute for Clinical and Experimental Medicine, Prague, Czechoslovakia.
Horácek
V
V
Kamarádová
S
S
D000098:Acetophenones / Q000494:pharmacology; D000818:Animals; D002867:Chromones / Q000494:pharmacology; D004285:Dogs; D005260:Female; D006439:Hemodynamics / Q000187:drug effects*; D007261:Infusions, Intra-Arterial; D007678:Kidney Glomerulus / Q000187:drug effects / Q000502:physiology*; D017999:Leukotriene E4; D008297:Male; D009399:Nephrons / Q000187:drug effects / Q000502:physiology; D013189:SRS-A / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors / Q000502:physiology*; D013777:Tetrazoles / Q000494:pharmacology
D000098:Acetophenones; D002867:Chromones; D013189:SRS-A; D013777:Tetrazoles; D017999:Leukotriene E4; C044660:LY 171883; C006312:FPL 55712