276 INTERNAL SECRETION 



chloride, the aurate of cholin is obtained. By crystallization twice 

 repeated, and by ascertaining the melting-point and the amount 

 of gold present, the insoluble aurate was found to be homogeneous 

 and was analysed. The result yielded by analysis was cholin 

 auric chloride. The aurate was converted into the chloride with 

 sulphuretted hydrogen, and this was employed in experiments 

 upon animals. It appeared that, when injected into the veins of 

 a cat in a quantity of .036 grm. in .5 c.cm. of Ringer's solution, 

 this cholin chloride produced a sudden fall in blood-pressure and 

 violent lachrymal and salivary secretion, followed by the death 

 of the animal. That the influence of cholin was antagonistic to 

 that of adrenalin was shown, not only by the effect upon the 

 blood-pressure, but also by the effect upon portions of intestine 

 removed from the living cat. The action of adrenalin in produc- 

 ing relaxation of the intestine was arrested by the addition of 

 cholin, and violent muscular contractions followed. In further 

 experiments, Lohmann tested the effects of adrenalin and cholin 

 upon the heart when taken from the living rabbit ; he found that 

 the increased and accelerated cardiac activity produced by 

 adrenalin was negatived by the weakening and slowing of the 

 contractions which followed cholin. The antagonism between 

 adrenalin and cholin was found to be mutual ; it was especially 

 noticeable that the profuse salivary flow produced by the sub- 

 cutaneous injection of cholin, was absolutely controlled by the 

 simultaneous injection of adrenalin. Lohmann was no more able 

 than Frank and Isaac later, to prevent the occurrence of adrenalin 

 glycosuria by means of cholin. According to Mansfeld, the sub- 

 cutaneous injection of cholin will arrest the development of the 

 changes in the vessels brought about by adrenalin. 



Lohmann next investigated the distribution of cholin in the 

 suprarenal and he discovered that it is possible to obtain nearly 

 nine times as much from the cortex as from the medulla. He 

 ascribes the cholin contents of the medulla to the presence of 

 cortical substance and arrives at the conclusion that, in the same 

 way that adrenalin is formed only in the medulla, so cholin is 

 formed solely in the cortex. 



Lohmann also described the manner in which he obtained 

 a further auric salt, by the slow concentration of the mother-lye 

 of the cholin auric chloride obtained from suprarenal extract. This 

 auric salt was crystallized and found to be neurin gold.* This 



* The constitutior.al formula of neurin (trimethylvinylammonium 

 hydroxyd) is as follows : 



CH 3 N 



This base is obtained from cholin by the splitting off of a molecule of 

 water out of the ethylalcohol, by which the latter is converted into the 

 vinyl residue. 



