vii KATABOLIC CONSTITUENTS OF UEINE 413 



Bouchard's results are important to the exact determination of 

 the urinary constituents on which the various toxic phenomena 

 depend, and may be shortly summed up : 



Urea, although present in large quantities in the urine, is 

 certainly not the chief poison. Injection of urea into the veins 

 produces toxic effects only when it is present in such an amount 

 and concentration that the osmotic pressure of the blood is 

 seriously altered (6'31 grms. urea per kilo, of the animal). In 

 moderate doses urea has a diuretic action, so that, far from acting 

 as a poison, it protects the body from auto-intoxication by acceler- 

 ating the expulsion of endogenous poisons. 



Nor can uric acid be regarded as a poison, since as much as 

 30 cgrms. per kilo, body weight -can be injected without effect. 

 Moreover, we know that man only forms 8 rngrms. uric acid per 

 kilo, in the 24 hours. 



Although elaborated by the .muscles in large quantities, the 

 innocuous character of creatine and creatinine has frequently been 

 demonstrated (Ranke, Schiffer). 



An alcoholic extract of the dry residue of urine certainly contains 

 toxic substances, seeing that intravenous injection of an alcoholic 

 solution induces drowsiness, coma, diuresis, salivation. At present 

 we are quite ignorant as to what constituent or compounds the 

 narcotic and scialagogic action depends on : all we can say is that 

 the diuretic action is due to urea. 



The urinary constituents which are insoluble in alcohol, on the 

 contrary, produce the opposite effects of convulsion, hypothermia, 

 rnyosis, without any symptoms of coma, salivation, or diuresis. It 

 is possible that these effects are due to the mineral substances. 

 Potassium salts, in fact, cause death with convulsive phenomena, 

 when injected to an amount of 0*5 grms. per kilo. Ammonium 

 salts also produce the same effect, but they are only present in 

 small quantities in the urine. It seems, however, as if we must 

 assume that there is in addition to these mineral poisons a substance 

 producing convulsions, which is represented by an organic con- 

 stituent insoluble in alcohol, seeing that night-urine produces 

 convulsive effects, which is not the case with the urine of waking, 

 even after muscular fatigue, when more mineral salts are 

 present. 



All the toxic effects obtained by intravenous injection of urine 

 into rabbits coma, convulsions, myosis, salivation, hypothermia 

 are also exhibited in the last stage of Bright 's disease, and in 

 the anuria of Asiatic cholera. The sole difference observed in 

 these spontaneous diseases as compared with the effect of experi- 

 mental injection of urine into the blood consists in the fact that 

 in the latter there is an abundant flow of urine promoted by the 

 urea, which, as we have seen, has a diuretic action that proportion- 

 ately alleviates the effects of the intoxication. 



