Neuroendocrine regulation in depressed postmenopausal women and healthy subjects

Results from prior studies utilizing gonadotropin-releasing hormone (GnRH) in affective illness have been contradictory. There have been no systematic investigations of multiple pituitary hormonal responses to GnRH infusion in either depressed or healthy postmenopausal women. Potential abnormalities in the hypothalamic-pituitary-gonadal (HPG) axis may be limited to postmenopausal women who lack the estradiol feedback influence at the pituitary level. We therefore studied 18 depressed and nine healthy postmenopausal women with the GnRH infusion test and measured LH, FSH, prolactin, growth hormone, and thyrotropin responses. Our findings confirmed earlier reports of a lower basal LH concentration in postmenopausal depressed subjects. GnRH stimulated release of LH, FSH, and prolactin in both patients and controls; however, there were no differences in the mean peak hormone values between groups.