246 Dr. C. Bolton. Further Observations on the [Nov. 16, 



proportion as the base is sclerotic the more difficult is it for the epithelium 

 to be regenerated and the glands to proliferate. It follows from this that the 

 delay in the healing of an acxde gastric ulcer is not so much due to a fault in the 

 epithelium as to the condition of the base of the tdcer over which it is growing. 



It was shown by Griffini and Vassale, as stated above, that the base of a 

 defect in the mucous membrane is covered with surface epithelium in 8 to 

 10 days if the animal eat no food for 4 to 5 days and is then put on milk, 

 but that regeneration of the epithelium has hardly commenced by the 8th to 

 12th day if it eat solid food from the first day. The condition of the gastric 

 contents is therefore of supreme importance in the healing of ulcer. In 

 pyloric stenosis, food saturated with gastric juice is retained beyond the normal 

 time. Excessive irritation and injury of the base of the ulcer results and 

 bacteria have more time in which to attach themselves to it, so that in the 

 early stages excessive exudation of leucocytes and perhaps necrosis of the 

 granulation tissue results, and in the later stages excessive fibrosis. The 

 former condition will delay the growth of the surface epithelium over the 

 base, and the latter will prevent the regeneration of the glands. This appears 

 to rae to be comparable to the failure of cancer to grow in an immune mouse, 

 the latter being unaljle to furnish a vascular stroma for the cancer to develop 

 in (9). It is conceivable that excessive formation of sclerotic tissue in the 

 base of the ulcer might completely prevent the growth of epithelium over it 

 in which case the ulcer would deepen from digestion of the fibrous tissue, but 

 of this I have no actual proof. Simple motor insufficiency will delay the 

 healing of an acute ulcer, but will not sto}) the liealing nor make the ulcer 

 extend. 



8. Eject of Motor Insufficiency upon the Size of the Ulcer. — A comparison 

 of the sizes and tendency to perforate of the ulcers produced in the above 

 cases of pyloric stenosis with those of the control animals shows that motor 

 insuihciency has no iniluence in increasing the sizes or tendency to perforate 

 of the ulcers produced. 



On the other liand, in G out of 29 cases there were considerable 

 haimorrliage and acute ulceration around the spot wliore the ulcer was 

 produced, and in all these ca.8os the gastric contents were alkaline or 

 neutral. This is undoubtedly a direct result of tlie pyloric stenosis, as 

 I liave never seen it apart from that condition. Whether or not it is due 

 to a secondaiy Itactcrial invasion of tbi; ulcer, I am not at jiresent in a 

 position to state. 



V. Coiifl iisions. 



1. A gastrotoxic serum active .against the cat may l)c prepared by 

 immunising the goat with cat's gastric cells. • 



