Orchidectomy Reduced Abdominal Aorta Relaxation Response to Androgens in Sprague Dawley Rats Fed a High Salt Diet

Abstract

The role of gonadal status on direct effect of androgens on isolated abdominal aorta from rats fed a high salt diet was assessed in this study. Twenty four weanling male rats were randomly divided into 4 groups (n = 6 each) that were either intact or orchidectomised and/or placed on normal (0.3%) or high (8%) NaCl diet. 3mm Aortic rings were suspended in organ baths containing Hepes buffer bubbled with 100% oxygen. Relaxation responses to testosterone propionate and dehydroepiandrosterone (DHEA) were studied in noradrenalin (0.1μM) pre‐contracted rings. MABP was determined before and weekly throughout the experimental period using non‐invasive tail cuff method. The results indicate a significant increase (P < 0.05) in the mean arterial blood pressure of rats placed on high salt diet, compared to controls while orchidectomy elicited a reduction in MABP (p < 0.05). There was a significant decrease (p < 0.05) in the relaxation response of rats placed on high salt diet to testosterone when compared with controls, while orchidectomy almost abolished relaxation response to testosterone (P < 0.001). Orchidectomy but not high salt diet significantly reduced (P < 0.001) relaxation response to DHEA. Thus orchidectomy reduces vascular relaxation response to androgens, and these effects were aggravated by high salt diet in male Sprague Dawley rat.