810 



215° and did not exhibit a lowering of the melting-point in the 

 mixture-experiment. For the melting point of the gold double salt 

 we found 238° — 239°, coiresponding with that of the gold-salt 

 prepared from pure cholin. 



Through some microchemical reactions we could also demonstrate 

 that we had to do here with cholin. With sodium gold chloride the 

 precipitate consisted of yellow obliquely truncated columns, completely 

 resembling those prepared from pure cholin ; with potassium mercury 

 iodide (Mayer's reagent) a double salt was given, crystallizing into 

 fine needles; likewise tlie precipitate with picrolonic-acid as well as 

 with potassium periodide looked outwardly like that obtained from 

 cholin. '^ 



Likewise the action upon the isolated rabbit's small intestine in 

 Tyrode fluid appeared to resemble that of cholin. 



A solution containing 0,3 nigrms of the compound isolated from 

 the small intestine, possessed a distinct influence upon the excised 

 rabbit's small intestine of about similar extent to the effect of 0,3 

 mgrms of' cholin-hydrochloride ; after heating with acetic acid anhydride 

 an amount corresponding with 0,003 mgrms of the detected compound 

 appeared to possess a considerable stimulating activity, approximately 

 similar to an equal amount of acetyl-cholin. 



This, then, proves that cholin is an active constituent of the 

 small-intestine extract. The quantity of cholin, derived in this way 

 as a mercurous double compound from the extract of a small- 

 intestine, amounts to about 1 mgrm. This is certainly not all the 

 cholin present in the primary aqueous extract, much less the total 

 amount in the intestinal wall, as we know that the precipitate, 

 obtained with acetone, contains also a small part of the active 

 substance. The alcoholic filtrate of the sublimate precipitate is always 

 more or less active and in this the presence of cholin can be readily 

 demonstrated, by means of the periodide test. By acetyl ating a greater 

 activity could be obtained, as with cholin, in the acetone precipitate 

 as well as in the alcoholic filtrate. Assuming that the activity of 

 these fractions, occurring with the isolation of cholin, may also be 

 ascribed to cholin, it appears that at least 75 7o of the looked for 

 active constituent of the rabbit's small intestine may be attributed 

 to cholin. However, I wish to accentuate that not in all experiments 

 such a high percentage of the cholin, present in the extracts, could 

 be isolated, as part of it gets lost more or less in the various 

 experiments. This was evident from the control-tests in which cholin 

 was added to the primarj^ extracts; after the usual experimentation 

 only part of the cholin could be found again. 



