The purpose of this study was to determine the effects of progesterone monotherapy or combined hormone replacement on the biomechanical properties of rat saphenous artery after ovariectomy. Adult virgin Sprague-Dawley rats were pharmacologically ovariectomised by triptorelin and received either 15 mg/kg medroxyprogesterone every two weeks, or the same treatment plus 450 ug/kg estradiol im. every week. Ten ovariectomised animals received no hormone therapy. Ten other animals were not ovariectomised (control group). After 12 weeks of treatment, cylindrical segments of the saphenous artery were isolated and cannulated at both ends. Pressure-diameter curves in the range of 0-200 mmHg were recorded from segments in normal KR, with norepinephrine (1.58×10-5M), and then with papaverine (2.84×10-5M). Pharmacological ovariectomy decreased, combined hormone replacement increased significantly the passive diameter of the arteries. Progesterone monotherapy did not alter the vessel diameter (internal radius at 100 mmHg IP:322±6um in the control, 300±9um in the castrated, 306±8um in the progesterone treated and 340±7um in the estrogen-progesterone treated groups, respectively, p<0.05). The reactivity to norepinephrine or papaverine was not changed significantly in any of the groups.
|Publication status||Published - Mar 20 1998|
ASJC Scopus subject areas
- Molecular Biology