ACID INTOXICATION 455 



Origin of the Acetone Bodies. As yet we are uncer- 

 tain as to the origin of these acetone bodies. Their close 

 chemical relation with one another makes it seem probable that 

 they have a common source, and it is also probable that they are 

 not abnormal products of metabolism, produced only in patients 

 with acid intoxication, but that they are formed normally in 

 metabolism, and accumulate when they cannot be destroyed as 

 they normally are, through oxidation. Acid intoxication, there- 

 fore, is dependent upon a failure of complete oxidation of 

 organic acids produced in metabolism. But whether the 

 acids are formed from fats, or from carbohydrates, or from 

 proteids, or from all three, has not been conclusively deter- 

 mined. Their chemical nature is such that they might readily 

 be produced from any or all of the three classes of food- 

 stuffs. 



They might be derived from carbohydrates, as is the closely 

 related lactic acid, but it is generally believed that this is not the 

 usual source, particularly because administration of a proper 

 amount of carbohydrates under certain conditions may cause 

 the acids to disappear from the urine, 1 and because the acids 

 may be eliminated in large quantities while the patient is on a 

 diet almost free from carbohydrates. 



They might readily be formed from proteids through splitting 

 out of the NH 2 group from the amino-acids, just as in acute 

 yellow atrophy we may find in the urine oxymandelic acid, 



HO/~~\CHOH COOH, 



derived from tyrosin, 



2 CHNH 2 COOH, 



by removal of the nitrogen-containing radical, with subsequent 

 failure of normal oxidation of the non-nitrogenous residue. 

 Indeed the amino-acids are generally considered as the chief 

 source of the acetone bodies, 2 particularly because whenever 

 there is considerable pathological breaking-down of proteids 

 these bodies, especially acetone, may appear in the urine ; e. g., in 

 patients with retained placenta or dead fetus, during absorption 



1 See Satta, Hofmeister's Beitr., 1905 (6), 376. 



2 Embden and his associates have recently (Hofmeister's Beitr., 1906 (8), 

 121) demonstrated that the liver can form acetone from many substances per- 

 fused through it in the blood, including not only amino-acids of the fatty acid 

 series, but also from the aromatic radicals of the proteid molecule. 



