Although other investigators have attempted to demonstrate that histamine has the power of producing acute ulcers when injected locally into the stomach wall, our experiments show clearly that this is a very inconstant finding for, of six instances, we were only able to obtain a small healed mucosal ulcer in one. Even when dilute acid (0.3 per cent hydrochloric acid) was fed to these animals they did not develop ulcers or erosions. It has also been stated that histamine, given subcutaneously, may produce ulcers secondarily to oversecretion of acid, especially when at the same time histamine has been injected into the stomach wall. We have been unable to confirm this observation.
In our series of experiments on dogs which were observed over a varying period of time ranging from 4 to 95 days we utilized other substances in addition to histamine. After establishing controls, sterile water, normal saline, 50 per cent glucose, skimmed milk, whole milk, omnadin, lipiodol, bismuth subcarbonate, pituitrin (S.), activin, histamine, adrenalin and insulin were injected into the muscular coat of the stomach and it was found that such procedures rarely produced any definite changes in the stomach mucosa even when supplemented by the feeding of dilute hydrochloric acid (0.3 per cent hydrochloric acid). We were able to demonstrate conclusively that the trauma involved in our operative procedure could not in itself account for any of the pathological findings. We were also able to show that the pressure due to the injected materials did not produce erosions or ulcerations. The injections of acids produced varying results. Diluted acid (0.3 per cent) injected into the stomach wall gave almost uniformly negative results but when combined with the feeding of acid of equal strength erosions were occasionally produced. Our results with 0.5 per cent hydrochloric add were also inconstant. The 1 per cent hydrochloric acid produced, in many instances, definite ulcerations even when not accompanied by the feeding of acid.