Insulin withdrawal impairs sexual receptivity and retention of brain cell nuclear estrogen receptors in diabetic rats.

Acute withdrawal of exogenous insulin significantly impairs estradiol and progesterone-induced sexual receptivity and retention of brain cell nuclear estrogen receptors in ovariectomized (OVX), streptozotocin-diabetic rats. Insulin withdrawal for 18--24 h of a 24 h estradiol benzoate (EB)-conditioning period resulted in significant reductions in mean lordosis ratings. Omission of insulin for any 12 h period during EB conditioning was without effect on sexual receptivity. 24 h insulin deprivation resulted in a signficant reduction of cell nuclear estrogen receptor levels in hypothalamus-preoptic area of rats sacrificed 26 h after EB administration. Withdrawal of insulin during the middle 12 h of conditioning had no significant effect on the quantities of brain cell nuclear estrogen receptors. These results are in agreement with the hypothesis that decreased cell nuclear binding of estradiol by neural target tissues may contribute to the reproductive dysfunctions of diabetics.