THE PITUITARY BODY 



parison with the number in the pituitary of animals killed 

 before or during hibernation. 



The pars glandularis of the rabbit, dog, sow, and rat has 

 been investigated at different times of the oestrous cycle to 

 determine what qualitative or quantitative histological 

 changes occur. ^ All the authors believed that they had ob- 

 served changes in the chromophils; and it is not surprising 

 that they were described as differing in different animals. 

 The pituitary of the rat, during the oestrous cycle, was the 

 only one studied in more than one laboratory. Reese found 

 that the oxyphils were intensely stained during metoestrus 

 (vaginal stage of cornification) but appeared to contain fewer 

 granules and to be lighter staining during dioestrus (corpus- 

 luteum phase). He observed no changes in the basophils. 

 Charipper and Haterius described a basophilia during oestrus 

 and a predominance of oxyphils during dioestrus. Finally, 

 Wolfe and Cleveland believed that "qualitative rather than 

 quantitative" cyclic changes could be observed, especially in 

 the oxyphils, similar to those described by Reese. Differences 

 in the appearance or the number of the chromophil cells at 

 different times of the oestrus cycle of the rabbit (including 

 pseudopregnancy), sow, and dog have been described by 

 Wolfe and Cleveland and their co-workers. 



Specific cells as sources of the hormones oj the pituitary body. 

 — The gonad-stimulating, growth-promoting, and thyro- 

 tropic hormones, as well as those more or less responsible for 

 the normal functioning of the adrenals, the pancreas, and 

 probably the parathyroids, seem to be elaborated in the pars 

 glandularis. The hormone responsible for the dispersion of 

 chromatosomes in the chromatophores of cold-blooded ani- 

 mals is produced by the cells of the pars intermedia (and pars 

 glandularis). The site of formation of the oxytocic and vaso- 



s Charipper and Haterius, Reese (1932); Cleveland and Wolfe, Wolfe and Cleve- 

 land, Wolfe, Cleveland, and Campbell (1933); W'olfe, Phelps, and Cleveland 

 (1934)- 



[28 1 



