[Hypothalamic LH-RH neuronal modifications after prolactine intraventricular infusion in the guinea pig (author's transl)].

Ovine prolactine injected at doses of either 31,25 to 500 microgram by lateral intraventricular route in male guinea pigs, affects LH-RH hypothalamic neurons within 2 to 24 hours. After this treatment there is an increase of LH-RH immunoreactive material in eminential terminals and in numerous small granules of hypothalamic neuronal cell bodies. This accumulation of immunoactive LH-RH in pericaryon and in terminals can be interpreted as stimulation of LH-RH synthesis. Preliminary results of radioimmunoassayed plasmatic LH level, 2 h after PRL infusion, are in agreement with this hypothesis. The probability that short feed-back by PRL or PIF secretion would simultaneously be able to check LH-RH secretion is discussed.