PTO MAINS 119 



Cholin itself is somewhat toxic, but the closely related body, 

 neurin, into which it may be transformed, is highly poisonous, 

 which makes cholin an important indirect source of intoxication. 

 It is possible, for example, that lecithin taken in the food splits 

 off cholin in the gastro-intestinal tract, and this being converted 

 into neurin gives rise to intoxication which may be ascribed to 

 food intoxication. Likewise it has been suggested that the 

 intoxication of fatigue may be due, at least in part, to cholin and 

 neurin produced from lecithin decomposed during the period of 

 cellular activity. The close structural relation to cholin and 

 neurin, of the mushroom poison, muscarin, which produces 

 physiological effects very similar to those of neurin, indicates 

 the close relationship of the putrefactive ptomams and the vege- 

 table alkaloids. Indeed a muscarin apparently identical with 

 that of the mushroom has been found in decomposing flesh, and 

 neurin, presumably derived from lecithin, may be found in 

 human urine. 1 Betain, the fourth member of the group, which 

 has but slight toxicity, is particularly well known as a constit- 

 uent of plant tissues ; possibly betain or other basic bodies may 

 occur substituted for cholin in certain varieties of lecithin (Lipp- 

 mann). 



Both neurin and muscarin are extremely poisonous and quite 

 similar in their effects. Subcutaneous injection of but 1 to 3 mg. 

 of muscarin in man produces salivation, rapid pulse, reddening of 

 the face, weakness, depression, profuse sweating, vomiting, and 

 diarrhoea. Neurin, likewise, causes salivation, lachrymation, 

 vomiting, and diarrhoea. In fatal poisoning respiration ceases 

 before the heart stops. Both poisons resemble physostigmine 

 in their stimulation of secretion and are equally well counter- 

 acted by atropin. The toxicity of these substances is so great 

 that not a large amount would need to be formed by oxidation 

 of cholin to produce severe symptoms, although it is not known 

 that this actually occurs in the body. When introduced by 

 mouth, the lethal dose of neurin is ten times as great as when 

 injected subcutaneously, indicating that chemical changes in the 

 gastro-intestinal tract offer some protection against intoxica- 

 tion by these substances when taken in tainted food. Cholin, 

 although by no means so poisonous as neurin, has a similar 

 action when administered in sufficiently large doses. Accord- 

 ing to Brieger, it is about one-tenth to one-twentieth as toxic as 

 neurin. 2 Cholin seems to be rapidly destroyed in the body, 



1 Kutscher and Lohmann, Zeit. physiol. Chem., 1906 (48), 1. 



2 Halliburton, "Chem. of Muscle and Nerve," 1904, p. 119, states that cholin 

 produces a fall in blood pressure by dilating the peripheral vessels, whereas 



