Effect of prostaglandin E2 on masculine sexual behaviour in the rat.

Intracerebral infusion of prostaglandin E2 (PGE2) facilitated copulatory behaviour of long-term castrated rats. Castrated rats were given daily systemic injections of testosterone propionate (50 microgram) or oil vehicle, and then 30 min before behavioural testing they received an intrahypothalamic infusion of either PGE2 or saline. Rats receiving PGE2 in addition to systemic testosterone showed more copulatory behaviour than those receiving PGE2 or testosterone alone.