Inhibition of lactation and prolactin secretion in rats by ergot alkaloids.

Abstract

Ergocornine hydrogenmalienate, 0.5 mg and 1.0 mg; ergonovine maleate, 4.0 mg; dihydroergocornine, 1.0 mg; ergotamine tartrate, 4.0 mg; and ergocryptine mesylate, 0.5 mg; were administered subcutaneously once a day to lactating postpartum female rats from day 4 postpartum (delivery = day 0) to day 8 postpartum. Serum prolactin levels as measured by radioimmunoassay were depressed significantly as a result of treatment with each ergot alkaloid when compared with corn oil treated control rats. These compounds significantly depressed lactation as assessed by litter weight gain. The total mammary tissue weight determined in each animal of an ergocornine hydrogenmalienate treated group showed a reduction compared to those animals in a control group receiving corn oil. Hypophysial homografts equivalent to 2 pituitary glands from donor litter mates were transplanted beneath the kidney capsules of mature hypophysectomized female rats 3 days after hypophysectomy. The rats were treated for 2 days with 0.5 mg ergocor...