[Hypothalamic mechanism of the antiovulatory action of sulpiride].

The antiovulatory effect of sulpiride is mediated via inhibition of the LH-RH release: when given during 10 days in guinea pigs, sulpiride is able to promote an increase of LH-RH immunoreactive substance in anterior hypothalamic and suprachiasmatic neurons. This storage probably related with inhibition of LH-RH release, is permitted by catecholamines, since metatyrosine administration prevent this sulpiride effect. On the other hand, when administered to hamsters sulpiride is able to promote stimulation of hypothalamic catecholaminergic neurons of tubero infundibular and anterior periventricularis nuclei. The hypothalamic aminergic action upon sulpiride antiovulatory effect is discussed.