Recently we made the electromyographic study on human gastrointestinal tract using the endoscopic method. This method is useful for the clinical studies of the patho-physiological aspects on human gastrointestinal tract.
The silver bipolar needle electrode which was 0.2 mm in diameter, 10 mm in length and 1.0 mm in interpolar distance and the electroencephalography recorder provided with pen-writer were used for this research. The endoscopy was done to the volunteer anesthetized his pharynx with xylocaine spray.
20 cases of gastro-electromyograms, 35 cases of duodeno-electromyograms and 5 cases of the electromyograms of duodenal papilla were recorded. On these endoscopic electromygorams, the typical rhythms and patterns of electrical activities were disturbed by various kinds of factors; that is, on the endoscopic manipulation, the sticking of needle electrode into the shallow layer of gastrointestinal wall and automatical pouring of water into canal through the endoscope. On volunteers' condition, his deep breathing, electrocardiogram and vasotonic condition were important factors.
Typical duodeno-electromyograms showed the grouped spikes synchronizing with the duodenal peristalsis observed endoscopically. The electromyograms of the duodenal papilla showed the similar patterns and rhythms to those of duodenoelectromyograms on active phase.
In the clinical study on the correlation and propagation between gastric and duodenal motility, the rhythms of electrical activities on duodeno-electromyograms were not similar to the rhythms of gastric peristalsis at the prepyloric region. The propagation of gastric movement to duodenal bulb were not able to be clarified. We assumed that the gastric and duodenal motility occurred each other on the different rhythms.

View full abstract

The gastric and intestinal motor function following pylorus preserving gastrectomy with jejunal interposition were studied electromyographically in dogs. The action potentials were recorded from the interposed jejunal segment, the preserving pylorus and the duodenum before and after insertion of warm water. Studies were made on the frequency, the propagation velocity of the spike-bursts in the portions mentioned above, and the incidence of the spike-bursts which propagated from the distal porition of the interposed jejunal segment to the preserving pylorus, and from the preserving pylorus to the proximal portion of the duodenum.
The results obtained are as follows:
1) The frequency of the spike-bursts found in the interposed jejunal segment, the preserving pylorus, and the duodenum showed a remarkable increase after insertion of warm water.
2) The propagation velocity of the spike-bursts in the interposed jejunal segment, the preserving pylorus, and the duodenum were accelerated after insertion of warm water.
3) There were observed a moderate increase in the incidence of the spike-bursts which propagated from the distal portion of the interposed jejunal segment to the preserving pylorus, and from the preserving pylorus to the proximal portion of the duodenum after insertion of warm water.
These findings suggested that the motor function of the interposed jejunalsegment, that of the preserving pylorus, and that of the duodenum after pylorus preserving gastrectomy with jejunal interposition might be kept not yet injured enough to transport the contents from the interposed jejunal segment into the duodenum.

View full abstract

The influences of the vagal inhibitory and excitatory reflexes on the gastric motor centers in the dog's medulla oblongata were investigated. Dogs were anaesthetized with Nembutal, and supplemented Gallamine at need. The brain stem was transected on the level of inferior colliculi of midbrain, the spinal cord transected on the level of between C₁ and C₂. Bilateral splanchnic nerves were also severed. Electrical activities from the inhibitory and excitatory areas in medulla oblongata were recorded by using a concentric circle electrode which was inserted into medulla oblongata from the dorsal surface of it. Following results were obtaind.
1) Electrical activities of the gastric inhibitory areas were classified into three types (see Table 1). Type I: The augmentation of electrical activities of the gastric inhibitory areas during the inhibitory reflex were associated with the diminution of them during the excitatory reflex.
Type II: Although electrical activities of the gastric inhibitory areas were augmented during the inhibitory reflex, any changes of them were not obtained during the excitatory reflex.
Type III: Any changes of electrical activities of the gastric inhibitory areas were not obtained during both inhibitory and excitatory reflexes.
2) Electrical activities of the gastric excitatory areas were classified into two types (see Table 2).
Type I: The diminution of electrical activities of the gastric excitatory areas during the inhibitory reflex were associated with the augmentation of them during the excitatory reflex.
Type II: Although any changes of electrical activities of the gastric excitatory areas were not observed during the inhibitory reflex, they were augmented during the excitatory reflex.

View full abstract

Twelve adult dogs fasted over night were used under Nembutal anesthesia. The intragastric pressure was measured by strain-gauge method with open tip cannula via duodenum. The stomach was filled through the cannula with 50 ml of Ringer's solution in a stepwise manner every two minutes until a total of 600 ml.
Following results were obtained:
1) The intragastric pressure was more elevated on the vagotomized and the splanchnicotomized dogs than on the intact animals by a stepwise augmentation of Ringer's solution.
2) On the animals which were transected totally the extrinsic nerves, the increase of the intragastric pressure was the most.
3) It may be concluded that the elevation of intragastric pressure after denervation of the extrinsic nerves, due to the abolitions of vagal and splanchnic inhibitory reflexes.

View full abstract