Faculty Collaboration Database

Evidence for the presence of smooth muscle alpha-actin within pericytes of the renal medulla. Am J Physiol 1997 Nov;273(5):R1742-8

Date

12/31/1997

Pubmed ID

9374818

DOI

10.1152/ajpregu.1997.273.5.R1742

Scopus ID

2-s2.0-0030723250 (requires institutional sign-in at Scopus site)   87 Citations

Abstract

This study was designed to determine whether smooth muscle alpha-actin mRNA and smooth muscle alpha-actin contractile protein elements were present within the renal medullary pericytes. Extraction of total RNA from microdissected outer medullary descending vasa recta allowed for the detection of smooth muscle alpha-actin mRNA expression using reverse transcription-polymerase chain reaction (RT-PCR). Expression of smooth muscle alpha-actin was specific to the descending vasa recta and not a result of tubular contamination because RT-PCR amplification of the vasopressin V2 receptor, which is a specific tubular marker, did not occur. To determine the exact cell type(s) that translate the mRNA into protein, we performed immunohistochemistry on the renal outer and inner medulla using a monoclonal smooth muscle alpha-actin antibody, whose specificity was determined by immunoblot analysis. Smooth muscle alpha-actin protein was found selectively within the pericytes surrounding the descending vasa recta from the outer and inner medullary tissue sections. This study demonstrates that the pericytes alone that surround the descending vasa recta within the outer and inner medulla contain smooth muscle alpha-actin mRNA and protein and are therefore the site of the contractile elements that could play a vasomodulatory role in the control of renal medullary blood flow and its distribution within the renal medulla.

Author List

Park F, Mattson DL, Roberts LA, Cowley AW Jr

Author

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

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

Actins
Animals
Arterioles
Blotting, Western
Capillaries
DNA Primers
Kidney Medulla
Male
Muscle, Smooth
Muscle, Smooth, Vascular
RNA, Messenger
Rats
Rats, Sprague-Dawley
Transcription, Genetic