title: Age-dependent renal responses to the bradykinin B(2)- receptor antagonist icatibant in conscious lambs.
abstract: To investigate the role of endogenously produced bradykinin in modulating renal function during postnatal maturation, various parameters of glomerular and tubular function were measured for 1 h before and after intravenous injection of 12.5 microg/kg of the specific B(2)-receptor antagonist icatibant to conscious, chronically instrumented lambs aged approximately 1 (n = 7) and approximately 6 wk (n = 7). In response to icatibant, and in the absence of any changes in renal hemodynamics, there was an approximately 80% decrease in glomerular filtration rate (GFR) at 20 min in 1-wk-old lambs that was sustained for 60 min; in 6-wk-old lambs, there was an approximately 70% decrease in GFR by 20 min, with control levels being reached by 40 min. Icatibant administration was also associated with significant decreases in urinary flow, Cl(-), and K(+) excretion rates that were similar in both groups of lambs, whereas Na(+) excretion decreased only in 6-wk-old lambs. We conclude that bradykinin modulates glomerular and tubular function in an age-dependent manner.
authors.affiliation: Departments of Physiology and Biophysics/Medicine, University of Calgary, Calgary, Alberta, T2N 4N1 Canada.
authors.forename: A
authors.initials: A
authors.lastname: Patel
authors.forename: F G
authors.initials: FG
authors.lastname: Smith
mesh_terms: D000375:Aging / Q000502:physiology*; D000818:Animals; D001920:Bradykinin / Q000031:analogs & derivatives / Q000494:pharmacology*; D065168:Bradykinin Receptor Antagonists; D002712:Chlorides / Q000378:metabolism; D003243:Consciousness; D004231:Diuresis / Q000187:drug effects; D005919:Glomerular Filtration Rate / Q000187:drug effects; D006400:Hematocrit; D006439:Hemodynamics / Q000187:drug effects / Q000502:physiology; D007668:Kidney / Q000187:drug effects* / Q000502:physiology*; D007684:Kidney Tubules / Q000187:drug effects / Q000502:physiology; D011188:Potassium / Q000378:metabolism; D011458:Prostaglandins E / Q000097:blood; D043782:Receptor, Bradykinin B2; D012083:Renin / Q000097:blood; D012756:Sheep
chemical_list: D065168:Bradykinin Receptor Antagonists; D002712:Chlorides; D011458:Prostaglandins E; D043782:Receptor, Bradykinin B2; C065679:icatibant; D012083:Renin; D011188:Potassium; D001920:Bradykinin