GLYCOCYAMINE AND GLYCOCYAMIDINE 79 



given to rabbits by the mouth, appears in the urine as creatinine and as 

 creatine in the muscles. His pupil Dorner [1907] confirmed these 

 results, using Folin's method. Glycocyamidine given subcutaneously 

 was also changed in rabbits to creatinine. Mellanby [1908] however 

 failed to observe any effects of glycocyamine feeding. 



/NH 2 

 C. Guanidine, NH:C< 



\NH 2 



Guanidine has been isolated from Vicia seedlings by Schulze [1892, 2] (i grm. of the 

 nitrate from 3 kilos.) but it could not be obtained from the ungerminated seeds. A small 

 quantity also occurs in the sap of sugar beets (Von Lippmann [1896]). It is further ob- 

 tained in the autolysis of pancreas (Kutscher and Otori [1904]) and by oxidation of 

 guanine and of various proteins with permanganates. Probably the " urea " obtained in 

 the oxidation of egg white by Bcchamp [1857] was in reality guanidine ; its formation in this 

 manner was first established by Lossen [1880]. Larger quantities were subsequently ob- 

 tained from various proteins, gelatin, casein, pseudomucin, thymus nucleic acid by Kutscher 

 and his collaborators [1903, 1904, 1905 ; Otori, 1904, 2] by using calcium permanganate, 

 and also in the case of pseudo-mucin by hydrolysis with acids (Otori [1904, i]). 



The physiological action of guanidine was investigated by Gergens 

 and Baumann [1876]. The base is a muscle poison affecting the 

 nerve endings (Camis [1909]). The effect is due to the univalent 

 guanidinium ion and resembles that of sodium salts (Fuhner [1908, 2]). 



/NH.CH 3 

 D. Methylguanidine, NH : C/ 



Methylguanidine is of greater physiological importance than 

 guanidine itself, being a normal constituent of muscle. It is formed 

 from creatine by boiling with mercuric oxide and dilute sulphuric acid 

 (Dessaignes [1854, 1855, nnder creatine], Gulewitsch [1906]) and 

 from creatinine and potassium permanganate (Neubauer [1861, i]). 

 Brieger [1886, 1, p. 34] obtained it from putrid horse meat. Kutscher 

 [1905, under creatine] and Gulewitsch [1906] isolated it from com- 

 mercial extract of meat (yield of the nitrate 0^38 per cent.; Gulewitsch). 

 According to Krimberg [1906, i] methylguanidine occurs in fresh beef, 

 where, however, Brieger [1886, I, p. 41] could not find it. Smoro- 

 dinzew [1913, Ch. II, carnosine] obtained 0*083 per cent, of methyl- 

 guanidine from fresh horse meat. Small quantities of methylguanidine 

 also occur in normal human urine (Kutscher and Lohmann [1906, 3], 

 Engeland [1908, 3]), in that of the dog after feeding on meat extract 

 (Kutscher and Lohmann [1906, 4]) and in that of the horse (Achelis 

 [1906]). Smorodinzew [1912] recently obtained the base from 

 liver. In the urine of parathyroidectomised dogs the amount of 



