ACTIVE PRINCIPLES OF INTERNAL SECRETIONS 197 



small quantities which are obtainable renders investigation of this 

 question by direct analysis a very difficult one. The free choline 

 alleged to have been detected in brain-tissue has been found to be a 

 postmortem product arising from autolysis or putrefaction. 



The physiological action of neurine is much more intense than that 

 of choline, being effective in about one twentieth of the dosage. By 

 introducing radicals into the oxyethyl group, however, as in Acetyl- 

 choline and the nitrous acid or nitric acid esters of choline, substances 

 of very much more intense physiological activity than choline itself 

 are produced. 



By the hydrolysis of the Cerebrosides, phrenosin and kerasin, a 

 nitrogenous base, Sphingosine is obtained the constitution of which is 

 at present unknown. Its percentage composition corresponds to the 

 formula Ci7H 35 NO 2 , and it is a diatomic alcohol containing an amino- 

 group. When sphingosine is heated with concentrated sulphuric acid 

 and a sugar, it yields a purple- violet coloration. The cerebrosides, 

 when similarly treated, first dissolve in the sulphuric acid, yielding a 

 clear yellow solution, and then the sphingosine is split off and sepa- 

 rates out in droplets which yield the reaction. The addition of sugar 

 in this case is unnecessary because it is supplied by the galactose in 

 the cerebroside. Regarding the physiological actions of sphingosine 

 nothing definite is known. 



NITROGENOUS BASES FORMING THE ACTIVE PRINCIPLES OF 

 INTERNAL SECRETIONS. 



Of these the best studied and, therefore, the best known is Adrenaline, 

 the blood-pressure raising or Pressor principle of the Suprarenal Gland. 

 Other names by which this substance is designated in current literature 

 are Epinephrin, Adrenin and Suprarenin. The term adrenaline is that 

 most customarily used although epinephrin is also frequently employed. 



Adrenaline is a derivative of Catechol and possesses the following 

 constitutional formula : 



COH 



/\ 



HC COH 



HC CH 



\/ 



C 

 CHOH 



CH 2 .NH.CH 3 



Adrenaline. 



