Ergot-induced inhibition of pituitary tumor growth in rats

Daily injections of ergocornine or ergonovine, for 3 weeks, into rats carrying a prolactin- and growth hormone-secreting pituitary tumor (MtW15) induced significant regression or inhibition of tumor growth, whereas ergocryptine had no significant effect. Ergocornine caused a decrease in cells and a disappearance or pycnosis of nuclei in the tumor tissue, and a reduced concentration of prolactin in blood.