Studies on the effects of oestradiol, progesterone and some steroidal contraceptives on the adrenal cortex of albino rats

An investigation was carried out on albino rats in order to study the effects of estradiol, progesterone, and some of the different synthetically prepared steroid combinations on adrenocortical activity. Biochemical determination of adrenocortical alkaline phosphatase activity was carried out in normal female rats, ovariectomized rats, and ovariectomized rats injected with estradiol or progesterone. Also, adrenocortical alkaline phosphatase activity was determined in groups of rats given different contraceptive pills (lyndiol 2.5, lyndiol 5, gyn-anovlar, eugynon, and ovulen) 1 tablet/rat/day for a period of 2 weeks. No pathological findings were detected in rats given contraceptive pills for 2 weeks, but after 6 weeks of treatment, the animals started to die, and definite pathological changes were detected mainly in the liver, spleen, and lungs. It was determined that ovariectomy resulted in a decrease in the activity of the adrenal cortex. Progesterone had no effect, but estradiol injection caused a significant increase in the activity of alkaline phosphatase of the adrenal cortex to values exceeding that of normal females. There was an increase in the activity of the adrenal cortex with any of the pills. The increase was highest with lyndiol 2.5 and lyndiol 5 and least with ovulen. Histological investigation revealed a similarity between the glands subjected to the effects of oral contraceptives and those stimulated by adrenocorticotropic hormone, mainly in the narrowing or even absence of the zona glomerulosa.