750 URINE. 



reducing action upon alkaline copper solutions after cleavage with hydrochloric 

 acid. 



Besides traces of sugar and the reducing substances previously men- 

 tioned, uric acid and creatinine, the urine contains still other bodies of this 

 character. These latter are partiy conjugated compounds of glucuronic 

 acid, CeNioO?, which is closely allied to sugar. The reducing power of 

 normal urine corresponds, according to various investigators, to 1.5-5.96 

 p. m. glucose. That portion of the reduction belonging to glucose 

 alone is equal to 0.1-0.6 p. m. LAVESON 1 believes that of the total 

 reduction 17.8 per cent is due to sugar, 26.3 per cent to creatinine, 7.8 

 per cent to uric acid, and the remainder, nearly 50 per cent, is caused 

 by chiefly unknown bodies. 



Conjugated glucuronates occur, as indicated by FLUCKIGER and first 

 positively shown by MAYER and NEUBERG, in an exact manner, in very 

 small amounts in normal urine. They occur chiefly as phenol- and only 

 very small amounts of indoxyl- or skatoxylglucuronates. The quantity 

 of glucuronic acid obtained from the conjugated glucuronates is estimated 

 as 0.04 p. m. by MAYER and NEUBERG, and by C. TOLLENS and FR. STERNA 

 on the contrary it was found to be 2.5 p. m. or 0.37 gram per day. Besides 

 these conjugated glucuronates perhaps the urine sometimes contains the 

 urea glucuronic acid, the ureidoglucuronic acid prepared synthetically 

 by NEUBERG and NIEMANN. S 



Very large amounts of these conjugated glucuronates occur in the 

 urine, on the other hand, after partaking of various therapeutic agents 

 and other substances, such as chloral hydrate, camphor, naphthol, borneol, 

 turpentine, morphine, and many other substances. The elimination 

 of glucuronic acid may be markedly increased in severe disturbances of 

 the respiration, severe dyspnoea, in diabetes mellitus, and by the direct 

 introduction of large amounts of glucose. According to P. MAYER, 

 in the oxidation of glucose a part of it forms glucuronic acid, hence it is 

 to be expected that the glucuronic acid can in part be derived from the 

 glucose. As a conjugation of the glucuronic acid with other bodies, 

 such as aromatic atomic complexes, prevents the combustion of this 

 acid in the animal body, it ought to follow that after the introduction 

 of such an atomic complex in the body during a glycosuria a correspond- 

 ing reduction of the glucose elimination would take place with the 

 increased excretion of conjugated glucuronates. In order to prove 

 this possibility, O. LoEWi 4 fed dogs with camphor during phlorhizin 



1 Fliickiger, Zeitschr. f. physiol. Chem., 9; Laveson, Bioch. Zeitschr., 4. 

 2 Fluckiger, 1. c.; Mayer and Neuberg, Zeitschr. f. physiol. Chem., 29; Tollens and 

 Stern, Zeitschr. f. physiol. Chem., 67. 



3 Zeitschr. f. physiol. Chem., 44. 



4 Arch. f. exp. Path. u. Pharm., 47. 



