title: The effect of acute angiotensin II blockade on renal function in rats with reduced renal mass.
abstract: The effect of acute Ang II blockade on renal function in rats with reduced nephron number was assessed in micropuncture studies. The Ang II receptor blocker, losartan, was administered at a dose of 10 mg i.v. at two intervals following five-sixths renal ablation. At eight weeks following ablation, Ang II blockade (Ang IIX) increased sodium excretion [UNa V, Ang IIX 2.2 +/- 0.4 microEq/min; time control (TC) 1.0 +/- 0.3 microEq/min; P < 0.05] but did not reduce mean arterial pressure (AP, Ang IIX 142 +/- 6 mm Hg; TC 151 +/- 6 mmHg), glomerular transcapillary pressure (delta P, Ang IIX 50 +/- 1 mm Hg; TC 50 +/- 1 mm Hg), or urine albumin excretion (UAlb V: Ang IIX 149 +/- 18 micrograms/min; TC 168 +/- 20 micrograms/min). Similarly, at two weeks following ablation, Ang II blockade increased UNa V (Ang IIX 2.8 +/- 0.4 microEq/min; TC 0.5 +/- 0.2 microEq/min; P < 0.05) without reducing AP (Ang IIX 132 +/- 6 mm Hg; TC 140 +/- 7 mm Hg), delta P (Ang IIX 50 +/- 3 mm Hg; TC 48 +/- 2 mm Hg), or UAlb V (Ang IIX 32 +/- 3 micrograms/min; TC 36 +/- 10 micrograms/min). These findings indicate that within the remant kidney, Ang II promotes sodium retention but does not have an acutely reversible effect on glomerular pressure or permselectivity.
authors.affiliation: Department of Medicine, Palo Alto VAMC, California.
authors.forename: K
authors.initials: K
authors.lastname: Baboolal
authors.forename: T W
authors.initials: TW
authors.lastname: Meyer
mesh_terms: D000419:Albuminuria / Q000503:physiopathology; D000804:Angiotensin II / Q000037:antagonists & inhibitors* / Q000502:physiology; D000818:Animals; D001713:Biphenyl Compounds / Q000008:administration & dosage / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D006977:Hypertension, Renal / Q000209:etiology / Q000503:physiopathology; D007093:Imidazoles / Q000008:administration & dosage / Q000494:pharmacology; D007668:Kidney / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology*; D019808:Losartan; D008297:Male; D009318:Natriuresis / Q000187:drug effects / Q000502:physiology; D009392:Nephrectomy; D011677:Punctures; D051381:Rats; D017208:Rats, Wistar; D013777:Tetrazoles / Q000008:administration & dosage / Q000494:pharmacology; D013997:Time Factors
chemical_list: D001713:Biphenyl Compounds; D007093:Imidazoles; D013777:Tetrazoles; D000804:Angiotensin II; D019808:Losartan