Suckling Antidiuresis in Rabbits

Abstract

LITTLE direct evidence exists that the act of suckling stimulates the release of posterior pituitary hormone as is postulated in Petersen's¹ theory of the letdown of milk. Peeters et al.² reported a milking antidiuresis in cows which was simulated by intravenous injection of 4 mU. posterior pituitary extract. This dose had no effect on letdown in the cow. Turner and Cooper³ described a swelling of the mammæ in lactating rabbits with intravenous injections of 1 mU. posterior pituitary extract. Experiments were undertaken to find if suckling in rabbits evokes an antidiuretic response which might be attributable to the neurohypophysis.