684 ARTHUR ISAAC KENDALL 



The daily excretion of indican varies greatly, both in the period of life 

 and with the individual. Nurslings practically never excrete indican 

 (Soldin). Adults secrete up to 10-12 milligrams daily without symp- 

 toms (Folin and Denis). 



Indol acetic acid, resulting from an oxidative deamination of tryp- 

 tophan, is said by Herter to be the mother substance of the urinary pig- 

 ment, urorosein. Indol is absorbed from the intestinal tract and oxidized 

 in the body, chiefly apparently in the liver, to indoxyl: 



OH 



and excreted as the sodium or potassium salt, indoxyl sodium [potas- 

 sium], sulphonate, or indican. It is also excreted under certain conditions 

 paired with glycuronic acid. 



ONa ONa 



/ 



OH + H OS = O = O.S = O + H 2 O 



O 



Indoxyl sodium sulphonate 



Phenyl alanin undergoes decomposition similar to tyrosin, finally 

 being absorbed from the alimentary canal and paired with glycuronic acid 

 or with sulphuric acid. In the latter event, it becomes, together with 

 indican, phenol and paracresol, the principal ethereal sulphates of the 

 urine. Phenol, 13 and paracresol, resulting from the bacterial degradation 

 of phenyl alanin and tyrosin, are excreted in considerable amounts as 

 ethereal sulphates. Folin and Denis state that as much as 0.2 to 0.3 

 gram of phenol may be excreted through the urine daily by apparently 

 normal adults. None of the substances excreted as ethereal sulphates 

 appear to be very toxic, although long continued formation of them in 

 the alimentary canal may be associated with severe disturbances. At the 

 present time it may be stated that the formation of the mother substances 

 of the urinary ethereal sulphates is an indication of bacterial decompo- 

 sition of the products of gastro-intestinal digestion of proteins. This 



13 It is worthy of note that the body rids itself of phenol, cresol, and indol [products 

 arising from the bacterial putrefaction of protein] together with sulphuric acid, which 

 arises from the oxidization of the sulphur of protein, as non-poisonous ethereal sul- 

 phates. This combination of noxious products of protein degradation, with a minimal 

 withdrawal of sodium or potassium would appear to be a not unimportant method of 

 elimination of a fixed acid (sulphuric acid), without impairing to any marked degree 

 the alkalai reserve of the body. 







