SECTION OF THE PITUITARY STALK IN MONKEYS

Abstract

SUMMARY An attempt was made to separate the pituitary gland from the hypothalamus in eight mature female rhesus monkeys by placing a piece of polythene film between the cut ends of the pituitary stalk. One animal died shortly after operation. In two it was established that the stalk had not been divided, and normal menstrual cycles continued. In a fourth, normal cycles also continued in spite of extensive damage to the stalk. Amenorrhoea set in in three of the monkeys despite variable degrees of regeneration of hypothalamo-hypophysial vascular connexions. One animal underwent two phases of uterine bleeding in spite of complete structural and vascular separation of the pituitary gland from the hypothalamus. The neural process was found to be atrophic in each of the seven surviving animals, and all developed diabetes insipidus. The severity of the polyuria could be correlated with the amount of damage to the median eminence rather than to the stalk.