Chlorpromazine prevents the nutritional stress-induced implantation failure in mice

Implantaiton failure in newly inseminated mice induced by food deprivation for 48 h beginning at 10.00 hr on day 2 or day 4 post coitum was prevented by administration of chlorpromazine (CPZ), 150 mu g/female/day, for 5 days coincident with the beginning of inanition; most famales carried pregnancy to term and delivered viable young. It is suggested that the CPZ- induced release of hypophyseal prolactin sustained the corpora lutea during nutritional stress and protected implantation in females. The results support the view that depression of hypophyseal prolactin release is the key endocrine factor that causes implantation failure in food-deprived females.