Effects of corticosterone on the estrous cycle of female rat

Female who reached the puberty age will undergo normal physiological process which is menstruation. However, menstrual disorders such as menorrhagia, pre­ menstrual syndrome, oligomenorrhea and amenorrhea are commonly related to psychological stress. Prevalence of menstrual disorder associated with stress was 34.6% (Ekpenyong, et al., 2011). There is direct association between stress and prevalence of menstrual disorder. Corticosterone is a stress-related hormone which released by endocrine system when subjected to stress. Stress can give various adverse effects on female menstrual cycle such as irregularity of cycle, prolong the bleeding duration and missed periods (Fenster et al., 1999). This study was conducted using corticosterone, which is a type of steroid hormone produced by adrenal cortex. High stress level due to greater secretion of corticosterone aggravates the activity of hypothalamus-pituitary adrenal (HPA) axis (Rabine et al., 1990). This study emphasized on the effect of corticosterone on the estrous cycle of female rat. The method for determination of the estrous cycle was through observation of cells obtained from vaginal smearing. Result obtained from 18-day duration of cell's observation showed that corticosterone (25 mg/kg) led to prolongation of estrous cycle from 4 days in the controlled group to 5- 7 days in the experimental group.