Induction of Lactation in Rabbits with Reserpine.

Abstract

Twenty mature female rabbits were injected subcutaneously with 0.2 mg estradiol daily for 2 or 10 days, followed by a single intravenous injection of 1 mg reserpine/ kilo body weight into 10 animals. The other 10 rabbits served as controls. Nine of the 10 reserpine-treated rabbits came into lactation one week later while none of the controls produced milk. Four other rabbits were made pseudopregnant, and 15 days later 2 were injected as above with reserpine and 2 served as controls. Only the 2 reserpine-treated animals came into milk. Macroscopic and histological examination of the mammary glands of reserpine-treated rabbits previously injected with estrogen revealed extensive lobule-alveolar development with secretion in the alveoli, whereas controls injected only with estrogen showed an extension of the duct system with no alveolar growth. It is probable that reserpine induced an increased secretion and/or release of prolactin and perhaps of other hormones favorable to mammary growth and lactation. Reserpine has now been shown to increase the prolactin content of the pituitaries of control and estradiol-treated rabbits.