PTOMA'iNS 119 



obtain evidence that choline is of any sip;nificancc in either physiologi- 

 cal or patholofj;i('al processes. Normally the largest amounts by far are 

 obtained from the adrenals, which also seem to contain choline deriva- 

 tives of much greater physiological activity. Choline itself is some- 

 what toxic, but the closely related body, neurine, into which it may be 

 transformed, is highly j)oisonous, which makes chf)line an important 

 indirect source of intoxication. It is possible, for example, that 

 lecithin taken in the food splits off choline in the gastro-intestinal 

 tract, and this being converted into neurine 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 choline and neurine produced from lecithin decomposed during the 

 period of cellular activity. The close structural relation to choline 

 and neurine, of the mushroom poison, muscarine, which produces 

 physiological effects very similar to those of neurine, indicates the 

 close relationship of the putrefactive ptomains and the vegetable 

 alkaloids. Indeed a muscarine apparently identical with that of the 

 mushroom has been found in decomposing flesh, and neurine, presum- 

 abl}^ derived from lecithin, may be found in human urine. ^" Betaine, 

 the fourth member of the group, which has but slight toxicity, is 

 particularly well known as a constituent of plant tissues. 



Both neurine and muscarine are extremely poisonous and quite 

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

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

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

 arrhoea. Neurine, 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 counteracted by atropine. The toxicity 

 of these substances is so great that not a large amount would need 

 to be formed by oxidation of choline to produce severe symptoms, 

 although it is not known that this actually occurs in the body. When 

 introduced by mouth, the lethal dose of neurine is ten times as great 

 as when injected subcutaneously, indicating that chemical changes in 

 the gastro-intestinal tract or liver offer some protection against in- 

 toxication by these substances when taken in tainted food. Choline, 

 although by no means so poisonous as neurine, has a similar action 

 when administered in sufficiently large doses. According to Brieger, 

 it is about one-tenth to one-twentieth as toxic as neurine. ^^ Choline 



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



'' Halliburton, "Chem. of Muscle and Nerve," 1904, p. 119, states that choline 

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

 ine constricts the peripheral vessels; he uses this difference in phj'siological ef- 

 fect as a means of distinguishing the two substances. Injected into animals, 

 choline causes a considerable but transient decrease in the number of leucocj'tes 

 in the blood, followed later by an increase (Werner and Lichtenberg, Deut. med. 

 Woch., 1906 (32), 22). 



