PITUICYTES AND THE ORIGIN OF THE ANTIDIURETIC HORMONE1

Abstract
INTRODUCTION THE question of the secretory activity of the tissue elements in the pars nervosa and more specifically of the pituicytes has been treated by most authors (Pickford, 1945; O’Connor, 1947; Harris, 1948; Collin and Stutinsky, 1949) as an open one, since the cells of the neurohypophysis do not possess cytological characteristics peculiar to gland cells, and since past attempts to link the production of posterior lobe hormones to microscopically visible changes in the pituicytes had failed. Gersh (1938, 1939) and Gersh and Brooks (1941), for instance, believed that they had shown a relationship between the state of dehydration of their experimental animals and the presence in the pituicytes of granules which they could stain with osmic acid. However, Hickey, Hare and Hare (1941), De Robertis and Primavesi (1942), and Desclin (1947) were unable to confirm these findings. The observations of Wang (1938) which have been frequently cited as supporting the concept of a secretory function of the pituicytes were based on sections stained with the Hortega method which is not suitable for the study of the cytology of secretion.