Gender-specific protection from microvessel rarefaction in female hypertensive rats. Am J Hypertens 1998 Aug;11(8 Pt 1):998-1005
Date
08/26/1998Pubmed ID
9715794DOI
10.1016/s0895-7061(98)00114-9Scopus ID
2-s2.0-0031848394 (requires institutional sign-in at Scopus site) 13 CitationsAbstract
Epidemiologic studies reveal that women have a significantly lower age-adjusted morbidity and mortality from cardiovascular disease than men, suggesting that gender is a cardiovascular disease risk factor. The mechanism of the "gender protection" is unknown. In this study, we investigated the microvascular remodeling in reduced renal mass plus a high salt (4.0% NaCl) diet model of hypertension (RRM + HS). We hypothesized that women would be protected from the increase in blood pressure and from the microvascular rarefaction associated with RRM + HS hypertension. Studies were designed to determine whether female rats were less susceptible to changes in microvessel density during RRM + HS. Microvessel density was measured in male and female low salt (0.4% LS) sham-operated controls (Sham + LS) and after 3 days or 4 weeks of RRM + HS hypertension. The microcirculation of hind limb (medial and lateral gastrocnemius, plantaris, soleus) muscles was visualized using rhodamine-labeled Griffonia simplicifolia I lectin. Tissue sections were examined by videomicroscopy and microvessel density was determined by quantitative stereology. As shown previously, mean arterial pressure increased to 160 +/- 8 mm Hg and microvessel density decreased (>30% decrease in all beds) in male RRM + HS. In contrast, mean arterial pressure of female RRM + HS rats was modestly increased from 101 +/- 2 to 118 +/- 4 mm Hg. Despite previous results showing a reduction in microvessel density of both normotensive and hypertensive male rats on a high salt diet, microvessel density of female RRM + HS rats was not reduced at either time. These results suggest that gender protection in the RRM rat extends beyond an attenuation of the increase in pressure to an immunity from microvascular rarefaction.
Author List
Papanek PE, Rieder MJ, Lombard JH, Greene ASAuthor
Paula Papanek PhD, MPT, LAT, FACSM Associate Professor & Director of Exercise Science in the Exercise Science & Physical Therapy department at Marquette UniversityMESH terms used to index this publication - Major topics in bold
AnimalsBlood Pressure
Female
Hypertension
Male
Microcirculation
Muscle, Skeletal
Rats
Rats, Sprague-Dawley
Renin-Angiotensin System
Sex Factors
Sodium, Dietary