Investigations of the butylcholinesterase-containing cells of the adenohypophysis of the white-crowned sparrow,Zonotrichia leucophrys gambelii

Summary In the adenohypophysis of Zonotrichia leucophrys gambelii two types of cells with butylcholinesterase(BuChE) activity can be demonstrated histochemically. Type I occurs in the cephalic lobe of the pars distalis and in the pars tuberalis; it consists of oval and round cells. It is a distinctive cell type that is identical with the amphophilic cells described by Matsuo, Vitums, King and Farner (1969). Whereas castration or inhibition of thyroid gland activity causes only minor changes in these cells, blocking of adrenal cortex activity, or adrenalectomy, causes conspicuous hyperplasia and hypertrophy suggesting that these cells are involved in the production or release of ACTH. The second type, which occurs in both cephalic and caudal lobes, consists mostly of irregularly formed cells. Various observations indicate that it is a composite group, consisting, at least in part, of degenerating cells.These investigations were supported by grants from the National Institutes of Health (S ROI NB 06812) and the National Science Foundation (GB 5969) to Professor Farner.