THE ANATOMY OF THE PITUITARY BODY 



effect of an oestrogen on the pituitary varies in different 

 strains of mice. 



Selye, Browne, and Collip (1936) injected 4 mg. of pro- 

 gesterone into young, mature female rats for 12 days. This 

 treatment was followed by some reduction in the size of the 

 ovaries (23 per cent) and some increase in the pituitary's 

 weight (29 per cent). In the pars glandularis of the injected 

 animals there was found "a great number of small cells with 

 relatively dense chromatin." 



Testosterone (or its propionate) causes no pituitary hyper- 

 trophy (McEuen, Selye, and Collip, 1937) and in this respect 

 differs from oestradiol or oestrone. However, like the oestro- 

 gens it brings about a degranulation of the basophils (Wolfe 

 and Hamilton, 1937). 



Wolfe (1935) and Wolfe and Phelps (1935) reported that 

 the effects of prolan on the pars glandularis of the adult rat 

 resemble those of an oestrogen — i.e., loss of granules from 

 basophils (and oxyphils) and hyperplasia of reserve cells. Ap- 

 parently these changes are due to the liberation of oestrogen 

 or androgen from the gonad stimulated by prolan. In 1937 

 Wolfe stated that prolan prevented some of the similar effects 

 of oestradiol in immature female rats. In comparison with 

 the pituitary of animals given only oestradiol, that of animals 

 receiving both prolan and oestrogen was less hypertrophied 

 and contained more basophils which were normal in respect 

 of granules. 



The relationship between other glands of internal secretion and 

 the anatom y of the pars glandularis . i . The thyroid. — -The pars 

 glandularis of the rabbit increases about 50 per cent in weight 

 after thyroidectomy performed 159-333 days previously (van 

 Dyke and Chen, 1935). Franck (1936) stated that the ad- 

 ministration of thyroid extract or thyroxin (and, to a less 

 extent, adrenal cortical hormone) to guinea pigs causes a re- 

 duction of the number of granules in the oxyphils. The num- 

 ber of basophils containing granules was thought also to be 

 reduced. Franck also stated that an extract containing thyro- 



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