THE PITUITARY BODY 



ber of reserve cells was pathognomonic of hypothyroidism in 

 man. For a recent study of the pituitary of goitrous indi- 

 viduals, see the report of Scalabrino (1934). 



In the rat, guinea pig, and dog, thyroidectomy is followed 

 by no alteration in the amount of thyrotropic hormone in the 

 pituitary (Houssay, Novelli, and Sammartino, 1932; Kusch- 

 insky, 1933; and Hohlweg and Junkmann, 1933).'^ In the 

 rabbit, Chen and van Dyke (1934) did not find a striking 

 change after thyroidectomy. These findings are contrary to 

 what one might anticipate from the fact that gonadectomy 

 gives rise to an increase in the amount of gonad-stimulating 

 principle in the pituitary. The amount of gonad-stimulating 

 principle in the rat pituitary was considered by Smith and 

 Engle (1930) to be unaltered by thyroidectomy; on the other 

 hand, Evans and Simpson (1930) concluded that thyroid- 

 ectomy reduced the amount of gonad-stimulating hormone. 

 Both sets of experiments were performed in female rats and 

 do not aid in the interpretation of Schockaert's (1931) state- 

 ment that thyroidectomy improves the response of male 

 rats to gonad-stimulating extracts.^ Van Dyke and Chen 

 (1933, 1935) found that thyroidectomy in the rabbit reduced 

 the concentration of the ovulation-producing hormone in the 

 pituitary; despite the pituitary hypertrophy, the total 

 amount of the hormone causing ovulation also appeared to 

 be reduced. The data so far gathered indicate that thyroidec- 

 tomy has no important effect on the total amounts of either 

 thyrotropic or gonadotropic hormones in the anterior pitui- 

 tary. The amount of growth-promoting hormone in the pitui- 



' However, the pituitary of the young ovariectomized guinea pig is said to con- 

 tain more thyrotropic hormone than that of the normal young female (Loeser, 

 1934). The thyroid of the ovariectomized guinea pig appears, histologically, to be 

 secreting more actively. In respect to this change, Benazzi (1933) came to exactly 

 the opposite conclusion from his study of the thyroids of normal and ovariectomized 

 mice. 



* Thyroidectomy does not alter the response of the ovary to gonad-stimulating 

 extracts (Bourg, 1930; and Loeser, 1932). 



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