Chapter V 



THE CHEMISTRY OF EPINEPHRINE 



Epinephrine is found in highest concentration in the medul- 

 lary portion of the adrenal gland. Considerable controversy 

 once raged as to its occurrence in the cortex, some authors 

 maintaining that it was actually elaborated in the cortex and 

 merely stored in the medulla. This view was based on the 

 demonstration of epinephrine in the cortical cells. 278 This 

 presence of epinephrine in the cortex is attributable, however, 

 to its rapid diffusion, post mortem, from the medulla. If proper 

 care be taken to remove the gland from the body before the 

 circulation has stopped and immediately cut away the cortical 

 tissue, no epinephrine will be found in the cortex. The oc- 

 currence of epinephrine in other chromaphil tissues besides 

 the adrenal, its presence in the chromaphil bodies of certain 

 Selachian fishes in which the cortical tissue is present as a 

 separate organ, and finally its presence in the embryo, before 

 the fusion of the chromaphil and interrenal tissues, all speak 

 against the view that the cortex is involved in the elaboration 

 of epinephrine. Nor is there any valid evidence for the exist- 

 ence of a pharmacodynamically more potent precursor from 

 which epinephrine is formed. 



The epinephrine content of the adrenals varies from about 

 one-half to three milligrams per gram of adrenal tissue. Thus 

 a pair of human adrenals contains about 8 mgms. of epi- 

 nephrine. Both adrenals of the beef contain about 40 to 70 

 mgms., the pig, 9, dog, 2, cat, 0.5, and rat, 0.15 mgms. The 

 epinephrine content of the adrenals is variously given in the 

 literature depending upon the methods used for its determina- 

 tion. 638 



Epinephrine is also present in the chromaphil tissue in other 

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