THE PITUITARY AND THE THYROID 



thyroparathyroidectomized and probably died as a result of 

 parathyroid deficiency. All the evidence in favor of the view 

 that the anterior pituitary vicariously secretes a thyroid-like 

 hormone after thyroidectomy or in the presence of a thyroid 

 deficiency is anatomical and lacks the support of physiologi- 

 cal or biochemical evidence. Although Wells (1897), for ex- 

 ample, could detect about 0.004 per cent iodine in dried hu- 

 man pituitary, Simpson and Hunter (1910, 191 1) found only 

 traces of iodine in beef and sheep pituitary bodies. Sheep 

 pituitary bodies, removed 5-6 months after thyroidectomy, 

 contained no iodine even after iodides had been fed.^ 



Anatomical studies of the pituitary after thyroidectomy 

 have also been made by Stieda (1890), Hofmeister (1894), 

 Leonhardt (1897), Katzenstein (1899), Herring (1908), Ta- 

 tum (1913), Livingston (1914), Kojima (1917), Izumi (1922), 

 Hammett (1923, 1926^, Dott (1923), Satwornitzkaja (1926), 

 Poos (1927), Bryant (1930), and Pugliese (1931). Usually 

 hypertrophy of the anterior pituitary follows thyroidectomy 

 and is often more marked in the male than in the female. The 

 longer the period of thyroid deficiency, the greater is the hy- 

 pertrophy. Histologically the important changes (in the an- 

 terior pituitary) consist of a marked reduction in the number 

 of oxyphil cells and a hypertrophy of the reserve cells in 

 which there appear to be signs of degeneration (vacuoliza- 

 tion, karyolysis, etc.).^ Apparently the anatomical findings 

 can be interpreted better as indicating degenerative changes 

 in the anterior pituitary than as suggesting increased secre- 

 tory activity. In man and the dog similar changes have been 

 described in cretins or goitrous individuals. Berblinger 

 (1921), for example, considered that an increase in the num- 



5 Also see the reports of Seaman (1920); Frey (1934); Koppenhofer (1934); 

 and Sturm (1934). 



' Severinghaus, Smelser, and Clark (1934) stated that in the thyroidectomized 

 male rat the basophils resembled those following castration. Herring believed 

 that at least the early changes were limited to the pars intermedia and the pars 

 neuralis. 



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