title: Hemodynamic and natriuretic effects of bumetanide and furosemide in the cat.
abstract: Renal hemodynamic and natriuretic effects of bumetanide and furosemide were studied by clearance and micropuncture methods in cats. Furosemide (0.04-5.0 mg/kg i.v.) effects increased with increasing doses up to a maximal fractional sodium (FEna) and water (V/GFR) excretion of 23%. GFR and superficial single nephron GFR remained constant. Renal blood flow (RBF) increased up to 45% over control. A preferential increase in outer cortical RBF occurred at 5.0 mg/kg. Bumetanide (0.001-0.14 mg/kg i.v.) raised FEna and V/GFR maximally by 26%. Only at a supramaximal dose (0.69 mg/kg) did bumetanide raise RBF and depress filtration fraction. Probenecid (50 mg/kg i.v.) failed to block the natriuretic effect of bumetanide (0.025 microgram/kg-min) when infused into one renal artery but abolished the natriuretic action of furosemide (1.0 microgram/kg-min). Probenecid failed to displace the dose-response curve for bumetanide.
mesh_terms: D000818:Animals; D002034:Bumetanide / Q000008:administration & dosage / Q000494:pharmacology*; D002415:Cats; D004231:Diuresis / Q000187:drug effects; D004232:Diuretics / Q000494:pharmacology*; D005260:Female; D005665:Furosemide / Q000008:administration & dosage / Q000494:pharmacology*; D005919:Glomerular Filtration Rate / Q000187:drug effects; D007261:Infusions, Intra-Arterial; D007668:Kidney / Q000098:blood supply*; D008297:Male; D009318:Natriuresis / Q000187:drug effects*; D009399:Nephrons / Q000187:drug effects; D012039:Regional Blood Flow / Q000187:drug effects; D012077:Renal Artery
chemical_list: D004232:Diuretics; D002034:Bumetanide; D005665:Furosemide