title: Role of angiotensin II in renal hemodynamic functions during the initial stages of acute ureteral obstruction.
abstract: This investigation examines the role of Angiotensin II in renal hemodynamic functions during acute unilateral ureteral obstruction (UUO) in a dog model. An electro magnetic flow probe was utilized to assess renal blood flow while the arteriovenous extraction technique of technetium 99m DTPA was utilized for the assessment of changes in filtration fraction and glomerular filtration rate. The effects of Angiotensin II receptor blockade on renal hemodynamic functions during acute UUO was evaluated in six dogs and compared to acute ureteral obstruction without receptor blockade in seven dogs. Angiotensin II blockade with (Sar1, Thr8)-Angiotensin II during UUO led to a striking increase in renal blood flow that was significantly different in comparison to normalized values from UUO alone (+delta 63 +/- 17 vs. +delta 22 +/- 6% at 30 min; p less than 0.05). There were, however, no significant differences in the magnitude of the decrease in filtration fraction and glomerular filtration rate in comparison to UUO alone. This investigation demonstrates that Angiotensin II has an inhibitory effect on the initial increase in renal blood flow with acute UUO. The possibility of successful pharmacologic intervention in the setting of UUO can be examined using animal models similar to the one described here. Pharmacologic treatment in the setting of acute UUO in patients might permit better preservation of renal function.
authors.affiliation: Department of Diagnostic Radiology, University of Rochester Medical Center, New York 14642.
authors.forename: R W
authors.initials: RW
authors.lastname: Katzberg
authors.forename: P L
authors.initials: PL
authors.lastname: DiMarco
authors.forename: T W
authors.initials: TW
authors.lastname: Morris
authors.forename: P P
authors.initials: PP
authors.lastname: Harnish
authors.forename: R F
authors.initials: RF
authors.lastname: Graves
authors.forename: P A
authors.initials: PA
authors.lastname: Merguerian
authors.forename: J A
authors.initials: JA
authors.lastname: Ventura
authors.forename: H M
authors.initials: HM
authors.lastname: Proskin
mesh_terms: D000804:Angiotensin II / Q000037:antagonists & inhibitors / Q000502:physiology*; D000818:Animals; D001783:Blood Flow Velocity; D004285:Dogs; D005260:Female; D005919:Glomerular Filtration Rate; D006439:Hemodynamics; D007668:Kidney / Q000098:blood supply*; D007700:Kinetics; D008297:Male; D009942:Organometallic Compounds; D004369:Pentetic Acid; D012079:Renal Circulation; D013667:Technetium; D016284:Technetium Tc 99m Pentetate; D014517:Ureteral Obstruction / Q000503:physiopathology*
chemical_list: D009942:Organometallic Compounds; D000804:Angiotensin II; D013667:Technetium; D004369:Pentetic Acid; D016284:Technetium Tc 99m Pentetate