616 CHEMICAL PATHOLOGY OF THE DUCTLESS GLANDS 



rest of the chromaffin substance remains to compensate.^* Chemically 

 the cortex is characterized by not containing the specific vaso-constrictor 

 principle, the epinephrine, and by containing a very large proportion of 

 lipoids. Thus, in water-free human adrenals (cortex and medulla 

 both included) there was found 36.3 per cent, of ether-soluble material, 

 of which 20.6 per cent, was cholesterol and 33 per cent, was phospholi- 

 pins.*^ The proportion of fats and lipoids varies greatly during changes 

 of age, disease, and perhaps of function, and there are those who beheve 

 the adrenal cortex to be a chief source of the hpoids of the blood, to 

 which much important function is ascribed in the reactions of immu- 

 nity. (See Lipoids, under Fatty Metamorphosis.) When cholesterol 

 is fed in large amounts some is deposited in the adrenal cortex,^" 

 while in many diseases, notably delirium tremens (Hirsch,)^' the lipoid 

 content of the adrenals is greatly decreased. In renal and arterial 

 disease the adrenal lipoids have been found increased.^- The lipins 

 of the adrenal cortex are said to contain little or no neutral fat,*^ but 

 free fatty acids which may be increased when the cholesterol de- 

 creases. Loss of body fats is not accompanied by a loss of adrenal 

 lipoids ordinarily, although they decrease in acute infections, especially 

 pneumonia. ^^ A vaso-depressor effect is produced by extracts of adre- 

 nal cortex, perhaps caused by choline which has been found in such 

 extracts, or possibly by histamine. 



The medulla is characterized, besides, by its pigmentary content, 

 by the remarkably active internal secretion, epinephrine,^^ which it 

 always contains in greater or less amount. Presumably epinephrine, 

 of which the formula is 



ho/ y HOH— CH2(NH)— CH3 

 H0~ 



is derived from the aromatic radical of the proteins, its close relation- 

 ship to tyrosine being seen when the formula of the latter is compared 



H0<^ NcHa— CH(NH2)— COOH 



That epinephrine is formed from tjTOsine directly, is, however, 

 not yet demonstrated. There are also other amines and aromatic 



^8 See Fulk and MacLoed (Amer. Jour. Physiol., 1916 (40), 21) who found 

 that the active principle of other chromaffin tissues has the same physiological 

 effect as that of the adrenal medulla. 



*'> Wells, Jour. Med. Res. 1908 (17), 461. 



"'" Krylov, Beitr. path. Anat., 1914 (58), 434. 



^' Jour. Amer. Med. Assoc, 1914 (63), 2186. 



" Chauffard, Compt. Rend. Soc. Biol., 1914 (76), 529. 



" Borberg, Skand. Arch. Physiol., 1915 (32), 287. 



" Elliott, Quart. Jour. Med., 1914 (8), 47; Laignel-Lavastine, Compt. Rend. 

 Soc. Biol., 1918 (81), 324. 



'' This name, given by Abel and Crawford, is to be preferred to the others in 

 common use, especially the most-used term "adremilin," which has been copy- 

 righted by a manufacturing establishment so that this name means specifically 

 their product, and not the active principle of the adrenal from whatever source. 



