Rapid microvessel rarefaction with elevated salt intake and reduced renal mass hypertension in rats. Circ Res 1996 Aug;79(2):324-30
Date
08/01/1996Pubmed ID
8756011DOI
10.1161/01.res.79.2.324Abstract
To identify the sequence of events associated with the development of reduced vessel density (rarefaction) in hypertension, microvessel density and ultrastructure were assessed in the cremaster muscle of rats subjected to a 75% surgical reduction of renal mass and normotensive sham-operated control rats. Rats with reduced renal mass (RRM rats) and sham-operated rats were then maintained on either a high salt (4.0% NaCl) or a low salt (0.4% NaCl) diet for 3 days. Acute exposure to the high salt diet significantly increased mean arterial pressure in RRM rats but did not affect sham-operated control rats. Quantitative fluorescence microscopy of cremaster muscle whole mounts using rhodamine-labeled Griffonia simplicifolia I lectin revealed substantial rarefaction of microvessels in both RRM hypertensive rats and normotensive sham-operated rats on a high salt diet relative to corresponding control rats on a low salt diet. Confocal microscopy revealed a heterogeneous distribution of microvessels in RRM rats on a high salt diet, with some areas largely devoid of vessels. RRM and sham-operated rats on a high salt diet both exhibited changes in arteriolar ultrastructure, which included a loss of basement membranes and a dissociation of the endothelial and smooth muscle components of the vascular wall, resulting in a loss of vessel integrity. These observations demonstrate that a rapid loss of microvessels can occur not only in rats with RRM hypertension but also in normotensive rats on a high salt diet. This loss of microvessels results from structural alterations, which differ from the degenerative processes associated with microvascular rarefaction in rats with chronic RRM hypertension.
Author List
Hansen-Smith FM, Morris LW, Greene AS, Lombard JHMESH terms used to index this publication - Major topics in bold
AnimalsBlood Pressure
Blood Vessels
Body Weight
Heart Rate
Hypertension
Male
Microcirculation
Microscopy, Electron
Microscopy, Fluorescence
Muscles
Nephrectomy
Rats
Rats, Sprague-Dawley
Sodium Chloride
Time Factors
