CHROMOGEN OF PANCREA TIC DIGESTION. 42 7 



decomposition. Lysine forms a platinochloride (C G H 14 Is T 2 2 , H 2 PtCl 6 + 

 C 2 H 5 OH) which is insoluble in 50 per cent, alcohol, in which the corre- 

 sponding lysatine salt is soluble, and by this means the two bases may be 

 separated ; or they may be separated by means of the difference in solubility 

 of their silver salts. 1 



Lysine, C 6 H 14 1S T 2 0.,, in composition corresponds to a diamido-caproic acid 

 (C f) H 9 (NH 2 ) 2 COOH) ; its solutions are dextrorotatory, but, like leucine and 

 glutamic acid, become inactive when heated with baryta water to 150 C. The 

 salts of lysine are crystalline, but the base itself has not been obtained in a 

 crystalline form. 



Lysatme or lysatinine yields a crystalline silver salt of the composition 

 C 6 H 1S N 3 O 2 , HNO.j + AgN0 3 , from which the formula of the base follows as 

 C G H 18 N 3 , except, as is supposed probable, the silver salt contains a molecule 

 of water of crystallisation, in which case the formula of the base would be 

 C (5 H 11 jS T 3 0. With the former formula it would be homologous with creatine, 

 with the latter homologous with creatinine, and would be most properly 

 called lysatine or lysatinine accordingly. 



Creatine is C 4 H S) N" 3 2 and creatinine is C 4 H 7 N 3 0. The new base may be 

 either lysatine with the formula C H 13 N 3 2 , or lysatinine with the formula 

 G 6 H n N 8 ; in either case being the second higher number in a homologous 

 series, that is differing in formula by (CH 2 ) 2 . 



Another similarity to creatine invests this organic base with its most 

 important physiological interest. Creatine when boiled with baryta water 

 splits up into sarcosin (or methyl-glycocoll) and urea ; similarly treated, 

 lysatine also yields urea. Drechsel treated the lysatine obtained from 

 10 grms. of the silver salt above referred to with excess of baryta water, 

 and obtained 1 grm. of urea nitrate, from which he isolated and identified 

 the urea. This is all the more interesting from the fact that creatine, 

 although it occurs in the body under such circumstances as leave little 

 doubt that it is formed as a decomposition product of proteids, has riot 

 yet been obtained artificially as a direct product of proteid decomposition. 

 Lysatine has not only been so obtained, but also as a product of pancreatic 

 digestion, and urea having been obtained from this, has consequently been 

 obtained as a product of proteid decomposition. 



Hedin 2 obtained from 3 kilos, of moist fibrin, 28 grms. of pure platino- 

 chloride of lysine, and enough of the silver salt of lysatinine to establish 

 its identity. 



Ammonia is found as a constant product in the artificial decomposition of 

 proteids, as might be inferred from what has been stated concerning lysatine, 

 and its formation has also been shown in pancreatic digestion. Hirschler 3 

 has shown that in the entire absence of putrefaction, in so short a period as 

 four hours, small quantities of ammonia appear in the pancreatic digestion of 

 fibrin ; this result has been confirmed by Stadelmann. 4 



The chromogen of pancreatic digestion. As early as 1831 it was 

 observed, by Tiedemann and Gmelin, 5 that the pancreatic juice of the dog takes 

 on a rose-red colour when mixed with chlorine water. Claude Bernard next 

 showed that no such reaction is obtained with fresh pancreatic juice, but first 

 appears after the juice has been kept for some time without putrefaction setting 

 in ; if putrefaction takes place, the reaction is also not obtained. The product 

 giving this colour reaction is now definitely recognised as a product of pancreatic 

 digestion, and not a constituent of pancreatic juice. For it the name trypto- 



1 For details of these processes see Gamgee, "Physiological Chemistry," London, 1893, 

 vol. ii. p. 255. 



-Arch.f. Anat. u. PhysioL, Leipzig, 1891, S. 273. 



s Ztschr. f. physiol. Chcm., Strassburg, 1880, Bd. x. S. 302. 



4 Ztschr. f. BioL, Mimclien, 1888, Bd. xxiv. S. 261. 



5 " Die Verdauung nach Versuchen," Heidelberg, 1831. 



