Neuroendocrine mechanisms mediating the suppression of circulating testosterone levels associated with chronic stress in male rats.

Neuroendocrine mechanisms involved in the reduction of testosterone (T) levels induced by the chronic surgical stress of s.c. gauze implantation were investigated in male rats. The reduction resulted from a decline in T secretion and not an increase in clearance of the hormone from the circulation. In most cases, the decrement was accompanied by a reduction in LH levels, indicating that decreased LH stimulation is the primary factor mediating the drop in T levels. The suppressive effect of surgical stress on LH and T levels was apparently not mediated by the pituitary-adrenal system.