title: Effect of estrogen and progesterone priming on the uptake and release of serotonin and noradrenaline from the ventromedial hypothalamus.
abstract: Estradiol benzoate (EB) or EB plus progesterone (P) were administered to chronic ovariectomized rats in doses which are known to induce sexual receptivity. P was injected 48 hr after EB and the animals were decapitated 54 hr after E.B. The ventromedial hypothalamus (VMH) (excluding the arcuate-median eminence region) was dissected out and used to determine 3H-noradrenaline (3H-NA) and 3H-serotonin (3H-5-HT) uptake and release induced by high potassium concentration. Animals injected with oil were used as controls. VMH from EB (10 micrograms/kg) plus P (2 mg/kg) primed animals had higher release of 3H-NE than controls; uptake and release of 3H-5-HT was also augmented in these animals. EB (100 micrograms/kg) priming alone did not induce significant variations. The increase in 3H-NA release is interpreted as evidence of incremented activity in a 3H-NA system, facilitating sexual receptivity. The change in 3H-5-HT uptake and release is discussed in respect to the existence of an inhibitory serotonergic system modulating sexual behavior.
mesh_terms: D000818:Animals; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D007033:Hypothalamus, Middle / Q000502:physiology*; D009638:Norepinephrine / Q000378:metabolism*; D011374:Progesterone / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism*; D012726:Sexual Behavior, Animal / Q000187:drug effects
chemical_list: D012701:Serotonin; D011374:Progesterone; D004958:Estradiol; D009638:Norepinephrine