Faculty Collaboration Database

Relationship between renal perfusion pressure and blood flow in different regions of the kidney. Am J Physiol 1993 Mar;264(3 Pt 2):R578-83

Date

03/11/1993

Pubmed ID

8457011

DOI

10.1152/ajpregu.1993.264.3.R578

Scopus ID

2-s2.0-0027483167 (requires institutional sign-in at Scopus site)   135 Citations

Abstract

The present study examined the autoregulation of blood flow in different regions of the renal cortex and medulla in volume-expanded or hydropenic anesthetized rats. Blood flow was measured in the whole kidney by electromagnetic flowmetry, in the superficial cortex with implanted fibers and external probes for laser-Doppler flowmetry, and in the deep cortex and inner and outer medulla with implanted fibers for laser-Doppler flowmetry. At renal perfusion pressure > 100 mmHg, renal blood flow, superficial cortical blood flow, and deep cortical blood flow were all very well autoregulated in both volume-expanded and hydropenic rats. Inner and outer medullary blood flow were also well autoregulated in hydropenia, but blood flow in these regions was very poorly autoregulated in volume-expanded animals. As renal perfusion pressure was decreased below 100 mmHg in volume-expanded and hydropenic animals, renal blood flow, superficial and deep cortical blood flow, and inner and outer medullary blood flow all decreased. The results of these experiments demonstrate that blood flow in both the inner and outer portions of the renal medulla of the kidney is poorly autoregulated in volume-expanded rats but well autoregulated in hydropenic animals. In contrast, blood flow in all regions of the renal cortex is well autoregulated in both volume-expanded and hydropenic animals. These results suggest that changes in resistance in the postglomerular circulation of deep nephrons are responsible for the poor autoregulation of medullary blood flow in volume expansion despite well autoregulated cortical blood flow.

Author List

Mattson DL, Lu S, Roman RJ, Cowley AW Jr

Author

Allen W. Cowley Jr PhD Professor in the Physiology department at Medical College of Wisconsin

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

Animals
Blood Flow Velocity
Blood Volume
Homeostasis
Kidney Cortex
Kidney Medulla
Laser-Doppler Flowmetry
Male
Pressure
Rats
Rats, Wistar
Renal Circulation