Abstract
Summary
The effect of an implant of prolactin in the median eminence (ME) on serum prolactin concentration was assessed in postpartum lactating rats and on the day of proestrus. An implant of prolactin in the ME of mother rats on the fourth postpartum day completely suppressed any rise in serum prolactin by the suckling stimulus from rat pups, and resulted in significantly lower litter weight gains than in similar non-prolactin-implanted control rats. An ME implant of prolactin by 10 am on the day of proestrus completely prevented the surge in serum prolactin normally observed on the late afternoon of proestrus. These results provide further evidence that high circulating levels of prolactin may serve to suppress pituitary prolactin secretion.
Get full access to this article
View all access options for this article.