Hormonal and monoaminergic influences on masculine copulatory behavior in the female rat.

Ovariectomized female rats receiving estradiol benzoate (EB), testosterone propionate, or no hormone treatment were administered parachlorophenylalanine (PCPA), alone, or in combination with pargyline. Sixteen days of EB-treatment resulted in hypertrophied pituitaries and concomitant pressure damage to ventral portions of the brain. Irrespective of hormonal condition females receiving PCPA treatment displayed more masculine copulatory behavior than females receiving PCPA + pargyline or saline treatment. In a second study PCPA also potentiated masculine copulatory behavior in ovariectomized and adrenalectomized females receiving no hormone treatment. The ejaculatory pattern was observed in one of eight females receiving EB + PCPA treatment and in two of seven ovariectomized-adrenalectomized females receiving PCPA treatment. The possible role of the hypothalamic-pituitary-adrenal system in the expression of the ejaculatory pattern in male and female rats is discussed.