PARS GLANDULARIS AND METABOLISM 



normal rats — or of an alkaline extract of fresh or desiccated 

 gland — can cause a marked hypertrophy of the spleen due 

 chiefly to hyperplasia and hypertrophy of the reticulo-endo- 

 thelial cells of the red pulp. In addition, there is some growth 

 of follicles, but the KupfFer cells are not affected. Hyper- 

 plasia of the reticular cells of the bone marrow likewise oc- 

 curs. Wetzler-Ligeti and Wiesner (1937) measured the effect 

 of anterior pituitary extract on the reticulo-endothelial sys- 

 tem by the rate at which Congo red was removed from the 

 blood after the dye had been injected intravenously. They 

 concluded that anterior pituitary extracts can either favor or 

 interfere with the removal of Congo red from the circulating 

 blood (positive and negative "restropic" effects). 



The relation of the pituitary to erythrocyte- (and leu- 

 cocyte-) formation was investigated by Kapran (1935) and 

 Flaks, Himmel, and Zlotnik (1937). Kapran reported on the 

 changes following hypophysectomy in the dog — i.e., di- 

 minished number of erythrocytes, elevated color-index, in- 

 terference with reticulocyte formation, slight leucopenia, and 

 eosinophilia even to 20 per cent; but that these changes were 

 specifically due to hypophysectomy was not shown. On the 

 other hand, McFarlane and McPhail (1937) were unable to 

 detect any change in erythrocyte count or content of hemo- 

 globin in guinea pigs because of the removal of the pituitary. 

 According to Flaks and his colleagues, a thermostable sub- 

 stance can be extracted from the anterior pituitary which di- 

 rectly stimulates the red bone marrow even after adminis- 

 tration by mouth. Reticulocytosis and later polycythemia 

 can be observed in rats receiving the extract. 



Keller and D'Amour (1936) occasionally found hemorrhage 

 into and ulceration of the gastrointestinal tract of dogs in 

 which hypophysectomy had been undertaken. However, 

 they were not certain that these pathological changes were 

 not caused by injury of the central nervous system. Belief 

 in the efficacy of heterotransplants of the anterior pituitary 

 was expressed by Kylin (1937), who concluded that they were 



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