THE PITUITARY BODY 



(1935) offer good evidence that such hyaHne bodies are fixa- 

 tion artefacts and are unrelated to the amount of pressor hor- 

 mone in the pars neuraHs. Gersh and Tarr studied the pars 

 neuraHs of six mammals and of the fowl. True secretory cells 

 have long been sought in the pars neuralis. Recently Gersh 

 (1937) described parenchymatous "glandular" cells more or 

 less uniformly distributed in the pars neuralis and containing 

 granules or lipoid droplets. They could be identified in the 

 neural lobe of nearly all mammals and of two birds (fowl and 

 pigeon). They appear to be supplied with nerve fibers passing 

 down the stalk and probably secrete the diuresis-inhibiting 

 (vasopressor) hormone. They were found to undergo degen- 

 eration after section of the stalk and to increase in number 

 and size if water was withheld. The brown and black pig- 

 ment of the human pars neuralis has been studied recently by 

 Roussy and Mosinger (1935). Trossarelli (1935) investigated 

 the connective tissue and nerve fibers of the pars neuralis. 

 He confirmed Tello's earlier description of the club-shape of 

 some of the nerve endings of the pars neuralis. Although true 

 nerve cells heretofore have not been identified in the pars 

 neuralis, Kasahara (1935) stated that nerve cells with grow- 

 ing fibers could be found in his cultures of pars neuralis tissue 

 obtained from young rabbits. The distribution of mast cells 

 in the infundibulum and pars neuralis of the ox, the cat, and 

 man has been studied by Gray (1935). The mast cells often 

 appeared to be closely associated with the primary capillary 

 network of the hypophysio-portal system. 



There have been no important additions to our knowledge 

 of the morphology of the pars tuberalis. Its functional im- 

 portance is still unknown, although Biggart believed that it 

 secretes the diuresis-inhibiting hormone. 



THE PARS GLANDULARIS 



As has already been mentioned, the majority of the recent 

 reports dealing with the anatomy of the pituitary body are 

 chiefly concerned with the physiological anatomy of the pars 



[12] 



