Presence of Vitamin B 1 in the Gastric Juice

Impaired functioning of the digestive system was for a long time known to be one of the earliest and most prominent manifestations of experimental vitamin-B deficiency. A diminution of gastric secretion was also reported repeatedly (Miyadera, 1 Shinoda, 2 Farnum, 3 Gilman 4 ). The data concerning the gastric secretion were however not very consistent, and furthermore there were considerable difficulties in interpretation for the reason that the experiments quoted above were complicated by many other factors, particularly by a loss of appetite and usually a high degree of inanition in the experimental animals. Recently it was demonstrated in this laboratory that a marked diminution of gastric secretion occurs in dogs on a diet lacking vitamin B even under conditions where the animals preserve an excellent appetite and well maintain their body weight (Babkin, 5 Webster and Armour 6 , 7 ). The withdrawal of yeast, as a source of vitamin B, from the standard diet practically abolished the gastric secretion in response to sham-feeding, to histamine, and to intra-intestinal administration of alcohol, as well as to introduction of food into the duodenum. The importance for normal gastric secretion of an adequate supply of vitamin B₁ was emphasized recently by Cowgill and Gilman. 8 The fact that with a diet lacking vitamin B the gastric glands are resistant to any kind of stimuli suggests that some of the factors concerned in vitamin B complex may play a vital part in the intimate mechanism of gastric glandular activity. In such a case one might expect the presence of such a factor also in the product of activity, i. e., in the gastric secretion.

The experimental study which we have carried out along these lines has indeed provided ample evidence that at least the anti-neuritic principle, vitamin Bi, is a normal constituent of canine gastric juice.