PARS GLANDULARIS AND ADRENAL GLANDS 



ly distributed as other hormones of the anterior pituitary. 

 Leonard (1937) concluded that it is present in the pituitary 

 of the fowl. ^According to the assays of McQueen-Williams 

 (1935) in rats, the anterior pituitary of the ox contains a 

 higher concentration of adrenal cortical stimulating hormone 

 than that of the rat. The author's preliminary experiments 

 indicated that the removal of both adrenal glands is followed 

 by an increase in the amount of the hormone in the pitui- 

 tary. 



Extracts of the anterior pituitary readily cause enlarge- 

 ment of the adrenal glands of normal or hypophysectomized 

 animals chiefly by bringing about hypertrophy of the cortex. 

 The effects of extracts in normal animals are, of course, 

 difficult to evaluate accurately because the pituitary is in- 

 tact. Among such observations are those of Bierring (1935), 

 Friedgood (1936), and Latyszewski (1937) who used rats, 

 guinea pigs, and rabbits. Bierring, who injected crude an- 

 terior pituitary extract into rats — sometimes for months — 

 considered that the important effect is on the zona glomer- 

 ulosa but that the three cortical zones were more clearly 

 demarcated in the treated animals. Some of Moon's observa- 

 tions (1937) also were made in normal rats. He reported that 

 cells of the glomerular and fasciculate zones underwent both 

 hypertrophy and hyperplasia after the injection of extract. 

 In the guinea pig, according to Friedgood, the left adrenal 

 undergoes more hypertrophy than the right. Latyszewski 

 did not feel convinced that the changes he observed in the 

 guinea pig and rabbit after the injection of extract were 

 specific or easily reproducible. The principal effects he de- 

 scribed were in the zona fasciculata and consisted of the loss 

 of lipoids and cellular hypertrophy affecting both the proto- 

 plasm and the nuclei. 



The effects of extracts in hypophysectomized animals are 

 more easily analyzed, because normally secreted cortical- 

 stimulating hormone is not an unknown and therefore con- 



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