Faculty Collaboration Database

Impaired autoregulation of renal blood flow in the fawn-hooded rat. Am J Physiol 1999 Jan;276(1):R189-96

Date

01/14/1999

Pubmed ID

9887194

DOI

10.1152/ajpregu.1999.276.1.R189

Scopus ID

2-s2.0-0032917634 (requires institutional sign-in at Scopus site)   57 Citations

Abstract

The responses to changes in renal perfusion pressure (RPP) were compared in 12-wk-old fawn-hooded hypertensive (FHH), fawn-hooded low blood pressure (FHL), and August Copenhagen Irish (ACI) rats to determine whether autoregulation of renal blood flow (RBF) is altered in the FHH rat. Mean arterial pressure was significantly higher in conscious, chronically instrumented FHH rats than in FHL rats (121 +/- 4 vs. 109 +/- 6 mmHg). Baseline arterial pressures measured in ketamine-Inactin-anesthetized rats averaged 147 +/- 2 mmHg (n = 9) in FHH, 132 +/- 2 mmHg (n = 10) in FHL, and 123 +/- 4 mmHg (n = 9) in ACI rats. Baseline RBF was significantly higher in FHH than in FHL and ACI rats and averaged 9.6 +/- 0.7, 7.4 +/- 0.5, and 7.8 +/- 0.9 ml. min-1. g kidney wt-1, respectively. RBF was autoregulated in ACI and FHL but not in FHH rats. Autoregulatory indexes in the range of RPPs from 100 to 150 mmHg averaged 0.96 +/- 0.12 in FHH vs. 0.42 +/- 0.04 in FHL and 0.30 +/- 0.02 in ACI rats. Glomerular filtration rate was 20-30% higher in FHH than in FHL and ACI rats. Elevations in RPP from 100 to 150 mmHg increased urinary protein excretion in FHH rats from 27 +/- 2 to 87 +/- 3 microg/min, whereas it was not significantly altered in FHL or ACI rats. The percentage of glomeruli exhibiting histological evidence of injury was not significantly different in the three strains of rats. These results indicate that autoregulation of RBF is impaired in FHH rats before the development of glomerulosclerosis and suggest that an abnormality in the control of renal vascular resistance may contribute to the development of proteinuria and renal failure in this strain of rats.

Author List

Van Dokkum RP, Alonso-Galicia M, Provoost AP, Jacob HJ, Roman RJ

MESH terms used to index this publication - Major topics in bold

Animals
Blood Pressure
Diuresis
Homeostasis
Hypertension
Hypotension
Kidney Glomerulus
Male
Natriuresis
Perfusion
Pressure
Proteinuria
Rats
Rats, Inbred ACI
Rats, Inbred Strains
Reference Values
Renal Circulation