[An experimental study on electric stimulation through the vagus on canine stomach (author's transl)]

The role of the vagus in gastric motility was studied by means of electric vagal stimulation in 44 dogs. Firstly the optimal electric current for vagus was examined, and then the stomach contraction at stimulation was recorded by strain gages. The effect of various agents at stimulation was observed too. The results obtained were as follows. 1. Optimal electric stimulus (duration=5 sec.) 1) frequency; 10 Hz or 50 approximately 60 Hz 2) voltage; 10 approximately 20 V or 30 approximately 50 V 3) width; 1 approximately 10 msec. 2. The canine stomach was proved the contraction gradient for electrical stimulus. 3. The central nerve system appeared to have an inhibitory effect on the vagus. 4. Stimulus for the single body branch could not evoke the contraction. 5. Antral branch stimulation evoked contraction of not only the antrum but also that of the body. 6. The pyloric branch did not play any significant role under the above mentioned stimulus. 7. The conduction of the neural stimulation was completely blocked by regional infiltration of xylocaine. 8. Reserpine and neostigmine increased excitability of the stomach. Gastric movement at stimulation was abolished on atropinization. These results indicate that the antral branch function favorably for the stomach body contraction. From the view point of enhancing the gastric motor (drainage) function, preserving the antral branch of the vagus is considered to support the advantage of selective proximal vagotomy technique.