Hormonal replacement therapy in an animal model with chronic renal failure and gonadectomy: Biochemical and hematological study

The aim of the present study was to investigate the effects of subcutaneous administration of estradiol propionate (450 mu g/kg female rat/day) or testosterone propionate (2 mg/kg male rat/day) for 4 weeks on some biochemical and hemato-logical variables in intact and gonadectomized male and female rats with chronic renal failure (CRF) induced by 7/8 nephrectomy (remnant kidney model). Twenty-four hours after the last injection, rats were decapitated and blood samples were collected for complete hemogram and for measuring the concentrations of creatinine, urea, and indoxyl sulphate in plasma. Body weights of all rats were taken every week during the experimental period. The hematological and biochemical parameters measured in the sham-operated and gonadectomized rats were not significantly different from those in intact rats. Induction of CRF significantly increased the concentrations of creatinine, urea, and indoxyl sulphate by about 90-300% (P < 0.05), and caused signs indicative of anemia. These effects were significantly exacerbated in gonadectomized rats with CRF, and were partially and significantly reversed by exogenous administration of testosterone/estradiol. The changes induced by CRF and gonadectomy on the hematocrit (HTC) and hemoglobin concentration (HGB) were more pronounced in females than in males. The HTC and HGB in gona-dectomized male rats with CRF were not significantly different from the controls. In the rest of the groups, there were no significant gender effects in the measured variables. It is suggested that, in the used rat model of CRF, there is depressed growth; significant increases in the plasma concentrations of creatinine, urea, and indoxyl sulphate; and anemia. All these signs were significantly and partially reversed by estradiol and testosterone therapy equally in female and male rats, respectively.