Chronic Estrogen Treatment Modifies Insulin-Induced Insulin Resistance and Hypertension in Ovariectomized Rats

Background Gender differences have been found in the development of hypertension. The role of estrogen in the association between hyperinsulinemia/insulin resistance and hypertension was investigated in an insulin-induced, insulin-resistant, and hypertensive model. Methods Ovariectomized or sham operated female Wistar rats were chronically treated with insulin and/or estrogen via subcutaneous implants (insulin, 2 U/day; 17β-estradiol 0.5 mg/pellet, 60-day release). Systolic blood pressure was monitored at weeks 0, 3, and 6. At week 7, an oral glucose tolerance test was performed. Results Ovariectomy resulted in the development ofinsulin resistance and blood pressure elevation in chronically insulin-treated female rats. Chronic estrogen treatment prevented the elevation in blood pressure and the development of insulin resistance. Conclusion The results indicate that chronic estrogen treatment modifies the insulin-induced hypertension by increasing insulin sensitivity in ovariectomized rats.