Effect of ergoline derivative VUFB-6638 on the adenohypophysial prolactin concentration in rats.

The compound VUFB-6638 (N-/D-6-methyl-8-isoergolin-I-yl/N'-N'-diethylurea hydrogen maleinate) was administered for four consecutive days to lactating rats in daily oral doses of 0.1, 1.0 and 2.0 mg/kg. The adenohypophysial prolactin concentration decreased by 34% to 68%, respectively. Moreover, this compound reduced or even completely suppressed the lactation. In view of the assumed relations between prolactin and breast carcinoma, a potential use of the drug is noted.