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On the Chemical Mechanism of Gastric Secretion. 
By J. S. Epxins, M.A., M.B. Cantab., Lecturer on Physiology in the Medical 
School of St. Bartholomew’s Hospital, London. 
(Communicated by Professor C. 8. Sherrington, F.R.S. Received May 13,— 
Read May 18, 1905.) 
It has long been known that the introduction of certain substances into 
the stomach provoke a secretion of gastric juice. This is regarded as in no 
sense depending upon mere mechanical stimulation of the mucous membrane, 
and it has been thought that the nervous mechanism of the gastric glands 
may be susceptible to certain local chemical stimuli. 
On the analogy of what has been held to be the mechanism at work in the 
secretion of pancreatic juice by Bayliss and Starling, it is probable that, in 
the process of absorption of digested food in the stomach, a substance may be 
separated from the cells of the mucous membrane which, passing into the 
blood or lymph, later stimulates the secretory cells of the stomach to 
functional activity. The following observations support this view :— 
If an extract in 5 per cent. dextrin of the fundus mucous membrane be 
injected into the jugular vein, there is no evidence of secretion of gastric 
juice. If the extract be made with the pyloric mucous membrane, there is 
evidence of a small quantity of secretion. With dextrin by itself there is no 
secretion. 
Extracts of fundus mucous membrane in dextrose or maltose give no 
secretion ; extracts of pyloric mucous membrane give marked secretion ; 
dextrose or maltose alone bring about no secretion. 
If extracts be made with commercial peptone, it is found that no secretion 
occurs with the fundus mucous membrane, a marked secretion with the 
pyloric mucous membrane; the peptone alone gives a slight secretion. 
If the extracts be made by boiling the mucous membrane in the different 
media, the effect is just the same, that is to say, the active principle, which 
may be called “ gastrin,” is not destroyed by boiling. 
Finally, it may bé pointed out that such absorption as occurs in the 
stomach apparently takes place in the pyloric end. With the pig’s stomach, in 
which the true cardiac region differs from the typical fundus region in having 
only simple glands as in the pyloric, extracts of the cardiac region in 
general have the same efficacy in promoting secretion, as do pyloric. 

