Adrenocortical response to 17-beta estradiol replacement in oophorectomized female sprague dawley rats.

Objective: To determine the effect of estradiol treatment on serum corticosterone levels in Oophorectomized (OVX) female Sprague Dawley rats exposed to chronic restraint stress.

Study Design: Experimental study.

Place And Duration Of Study: Department of Physiology, Army Medical College, Rawalpindi and National Institute of Health, Islamabad, from January to December 2008.

Methodology: A total of 90 female Sprague Dawley rats (age: 90 ± 10 days), were divided into three groups, each having 30 rats. Group-I comprised of healthy control female rats whereas group-II and III were experimental female rats exposed to chronic restraint stress after bilateral Oophorectomy and called estradiol treated and vehicle treated groups. Estradiol treatment of Oophorectomized rats was done once daily for 2 weeks. At the end of experiment, the rats were sacrificed and intracardiac blood sampling was done to measure serum corticosterone levels by enzyme linked immunosorbent assay (ELISA) kit.

Results: The restraint stress to estradiol treated rats for 2 weeks revealed that serum corticosterone levels were significantly increased (31.32 ± 5.46 ng/ml, p < 0.05) as compared to the healthy controls (17.48 ± 4.14 ng/ml).

Conclusion: Chronic restraint stress results increases the serum corticosterone levels in Oophorectomized Sprague Dawley rats. Estradiol treatment increases the responsiveness of adrenal cortex of Oophorectomized female rats.