Testosterone Enhances the Early Onset and Promotes the Increase in Magnitude of Salt-Induced Hypertension in Male Sprague-Dawley Rats

Blood pressure has been reported to be consistently higher in males compared with females from puberty onwards and men show an increased risk for hypertension compared to women, a risk that interacts with genes and with diet. Experiments were designed to assess the effect of testosterone deficiency on blood pressure in male Sprague-Dawley rats on normal or high salt diet. Weanling male rats were randomly divided into 8 groups (n = 6 each) that were either orchidectomised or sham-operated (under ketamine and xylazine anaesthesia), with or without testosterone replacement (10mg/kg sustanon 250® i.m once in 3 weeks), and were placed on normal (0.3%) or high (8%) NaCl diet for 6 weeks. Arterial blood pressure was determined before and weekly throughout the experimental period using non-invasive tail cuff method. There was a significant increase (P 0.001) in the mean arterial blood pressure of rats placed on high salt diet when compared with control or orchidectomised rats. Orchidectomy elicited a reduction in MABP while testosterone replacement normalized MABP to values observed in intact rats placed on high salt diet. Endogenous testosterone promotes blood pressure-elevating effect of a high salt diet.