title: Effect of kinin receptor antagonists on renal hemodynamic and natriuretic responses to volume expansion.
abstract: The role of kinins in the natriuretic and papillary blood flow (PBF) responses to intravenous administration of 0.9% sodium chloride solution equal to 5% of body weight over 30 min was evaluated using a B1-kinin receptor antagonist (des-Arg9, [Leu8]bradykinin, 2.5 micrograms/min i.v.) and a B2-kinin receptor antagonist (D-Arg, [Hyp3,Thi5,8,D-Phe7]bradykinin, 2.5 micrograms/min i.v.). In control rats, PBF increased 43 +/- 5% after the volume expansion with saline. Administration of the B1-kinin receptor antagonist had no significant effect on basal PBF or the rise in PBF produced by volume expansion. In contrast, administration of the B2-kinin receptor antagonist decreased basal PBF by 18 +/- 3% and prevented the rise in PBF during volume expansion. Urine osmolality was lower in the rats treated with the B1-antagonist and higher in rats infused with the B2-kinin antagonist than in control animals after volume expansion (587 +/- 47 and 1,082 +/- 83 vs. 907 +/- 124 mosmol/kgH2O, respectively). The initial natriuretic response during the first 30 min after volume expansion was similar in rats given vehicle or the kinin antagonists. However, cumulative sodium excretion over the 2-h course of the experiment was significantly lower in the rats given the B2-receptor antagonist than in control rats (92 +/- 7 vs. 101 +/- 9% of the administered load). The B1-kinin receptor antagonist had no effect on cumulative sodium excretion; however, glomerular filtration rate was 30% lower in rats receiving the B1-antagonist than in control rats after volume expansion.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Physiology, Medical College of Wisconsin, Milwaukee 53226.
authors.forename: F J
authors.initials: FJ
authors.lastname: Fenoy
authors.forename: R J
authors.initials: RJ
authors.lastname: Roman
mesh_terms: D000818:Animals; D001810:Blood Volume / Q000187:drug effects*; D004231:Diuresis / Q000187:drug effects; D004912:Erythrocytes / Q000502:physiology; D005110:Extracellular Space / Q000502:physiology; D006439:Hemodynamics / Q000187:drug effects; D006874:Hydrostatic Pressure; D007679:Kidney Medulla / Q000098:blood supply; D009318:Natriuresis / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains; D018002:Receptors, Bradykinin; D017981:Receptors, Neurotransmitter / Q000037:antagonists & inhibitors*; D012079:Renal Circulation / Q000187:drug effects*; D012965:Sodium Chloride / Q000494:pharmacology
chemical_list: D018002:Receptors, Bradykinin; D017981:Receptors, Neurotransmitter; D012965:Sodium Chloride