The effects of some dopamine-beta-hydroxylase inhibitors on the control mechanisms of the estrous cycle in rats.

Disulfiram (DS) administered in single doses of 200--400 mg/kg i.p. before the critical period of proestrus (9--11 h), or in diestrus--2 (20--23 h), induced in most animals prolongation of the estrus, i.e. an antiovulatory action. FLA-63 had the same effect in a smaller dose (2 mg/kg s.c.) DS elicited the ovulation-blocking action only in doses known to reduce the cerebral noradrenaline level. For the central site of DS action plead its efficacy after i.v.c. administration in a much smaller dose (1 mg/rat), the reduction of the uterine weight, as well as the lack of any significant influence of the drug on the peripheral actions of estradiol. The fact that the two DBH-inhibitors provoked mostly an antiovulatory effect supports the stimulatory role of adrenergic neurons in the control of LRF secretion, because DBH is present only in these neurons and not in the dopaminergic pathways.