My experiments lead me to believe that complete occlusion of the small intestine at its lower end will give rise to the occurrence of cholin, neurin and perhaps other bases, provided the food taken contains any considerable quantity of lecithin. It is not improbable that still other poisons are formed by bacterial action from other constituents of the food in cases of intestinal obstruction. While cholin would have to be absorbed in relatively large amounts to exert a marked toxic action in human beings it is otherwise with neurin, which is many times more intense in its action and must be classed with the exceedingly active poisons. It has been shown both by the experiments of Schmidt and Weiss and also by those recorded in this paper that the poisonous neurin may be formed from cholin by bacteria. In its physiological action neurin agrees closely with muscarin; especially to be noted here is the paralytic action on the heart and its power to increase the intestinal movements to such an extent that continual evacuations occur. Whether the ptomaine which was found by me is poisonous 1 cannot yet say. It must be considered proved, however, that highly toxic substances may arise in the intestinal canal during its complete occlusion. The method of treating cases of intestinal obstruction, before surgical means are resorted to, namely, washing out the stomach and as much of the gut as possible often reduces the violent paristalsis and this is due, perhaps, to the removal of substances out of which irritating and toxic products are formed by bacteria.
In conclusion, I would remark that our knowledge of the fate of lecithin in the digestive canal under normal conditions is very deficient. The assumption that it is saponified by the fat-splitting enzyme of the pancreatic juice, thus yielding cholin, glycero-phosphoric acid and fatty acids, rests on the work of Bókai in 1877 and, as that investigator himself admits, without excluding bacterial action. This omission throws grave doubts on the results. If the assumption of Bókai be correct, caution must be observed in the use of some foods that have been considered most nutritious and healthful; for instance, the ingestion of a meal made up largely of eggs would hardly be without danger because of the poisonous action of the large quantity of cholin liberated from the lecithin and the probability of the formation of the highly poisonous neurin.
It is my purpose in the near future to examine this question with the help of modern methods.