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A TEXTBOOK OF PHYSIOLOGY 







one of these secretions will alter the metabolic conditions of the 

 body, sometimes in an anabolic, sometimes in a katabolic direction. 



A possible example of this 

 interdependence has al- 

 ready been referred to 

 under carbohydrate meta- 

 bolism. It is suggested 

 that normally internal 8- 

 cretions from the pancreas, 

 suprarenal, thyroid, and 

 possibly other glands, help 

 to regulate carbohydrate 

 metabolism. When all 

 these are present in cor- 

 rect amounts, the meta- 

 bolism proceeds in orderly 

 fashion. If, however, the 

 balance be upset for ex- 

 ample, by too little of the 

 pancreatic secretion being 

 present then the kata- 

 bolism of sugar is de- 

 ranged. Too much sugar 

 therefore accumulates in 

 the blood, and the condi- 

 tion of glycosuria results. 

 In the development of 

 sexual characteristics a 

 balance between various 

 internal secretions is con- 

 cerned for example, the 

 testes or ovary, and the 

 suprarenal, thymus, and 

 in the female possibly the 

 thyroid gland. The action 

 of these internal secretions 

 has been investigated by 

 various methods, chief of 

 which are the extirpation, 

 transplantation of the 

 gland, and the injection 

 of gland extracts. Clinical 

 experience has yielded 

 valuable information. 



Although the exact 

 extent of the dependence 

 of the action of the various 

 to a large extent conjectural. 



i. 3 



internal secretions 

 the fact that such 



one on another 



an interworking does take place has been experi- 



