Chap. 15 CHEMICAL REGULATION ENDOCRINE GLANDS 267 



balance of sodium and potassium in the body. The second group (the 11- 

 oxysteroids) includes cortisone, exercises its particular effect on carbo- 

 hydrate and protein metabolism, and is involved in the series of adaptations 

 called the alarm reaction that occurs after stresses such as shock, extreme cold, 

 and poisons. Cortisone remedies adrenal deficiency either in experimental 

 animals with both cortices removed or in persons suffering from Addison's 

 disease in which the cortices have atrophied. The production of these hor- 

 mones is under the control of the adrenocorticotrophic hormone (ACTH) 

 of the pars anterior of the pituitary. The third group of hormones is very 

 similar to the sex hormones. Excess production of such hormones, often 

 associated with tumors of the cortex, is responsible for the bearded ladies 

 of the circus. 



Pancreas 



Endocrine Glands of the Pancreas and Their Function. Nothing takes the 

 place of the versatile digestive juice of the pancreas as an all-round simplifier 

 of foods that otherwise would be out of reach of the body's metabolism. But 

 the pancreas also contains numerous endocrine glands, literally islands of 

 cells, the isles of Langerhans, that secrete into the blood stream the hormone 

 insulin and possibly lipocaic, a hormone of fat metabolism. Insulin has been 

 called the spark-plug of carbohydrate metabolism because, in some way, it 

 brings about the oxidation of sugar and the subsequent release of potential 

 chemical energy (Fig. 15.12). 



Callblodd 



CHOLECYSTOKININ 

 secreted by 

 duodenum- 

 results in 

 emptying goll- 

 blodder 



ENTEROGASTERONE 

 Secreted by 

 lenum — 

 jostric 

 lotiljjy 



GASTRIN 



Secreted by 

 stomach- 

 stimulates stomach 



Pancreos 



SECRETIN 

 secreted by duodenum— 

 Stimulotes poncreos 



ENTEROCRININ 

 Secreted by duodenum— 

 stimulotes duodenum 



Fig. 15.12. Diagram of the structures from which digestive hormones originate 

 and the parts and processes which they stimulate. (Courtesy, Hunter and Hunter: 

 College Zoology. Philadelphia, W. B. Saunders Co., 1949.) 



