(1) In the large intestine its anterior half (ampulla) was full of its contents, while its posterior part (isthmus) was constricted to be wholly empty.
(2) It was found that on the bullfrog large intestine pulsations recurrently occurr-ed in the oral circumference of the orifice where the bladder was opened into the cloaca, traveling upwards the gut wall as shallow contraction waves (antiperistaltic waves), respectively.
(3) The 10th or 11th spinal nerve stimulation produced a remarkable excitation of the movements: Firstly an excessive shortening of the gut occurred to produce a shift of contents through the isthmus to the cloaca and was then followed by an excessive rise of tone superimposed with powerful antiperistaltic waves, occasionally a small amounts of contents being forced out of the anus. Such a movement might be considered to be a first stage of the defecation movement.
(4) Any sigh of the intrinsic mucosal reflex was not observed with the stimulation either of a spot or of the whole surface (by raising the intraluminal pressure) of the mucosa of the large intestine. These facts suggest that in the bullfrog the intramural ganglion cells have no function to regulate the strength as well as the direction of propagation of contraction waves.

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Using 64 mongrel adult dogs electromyographical studies on a location of possible pace maker and the propagation of action potential of gastric smooth muscles were performed.
The results were as follows;
1) The action potential arises from the first oblique muscle bundle which lies on the most external portion of the oblique muscle bundles.
2) Electromyographically, canine stomach can be divided into 3 areas as characterized by the structure of the smooth muscle layer, namely ringular muscle area, oblique muscle area and circular muscle area. The ringular muscle area locates on the fornix having no action potential. The oblique muscle area is central area which occupies between the first oblique muscle bundle and the border circular muscle bundle. This area is considered to have"pace maker" of isoperistaltic action potential. The circular muscle area locates on the most distal part, working as a rout of propagation of action potential. And it is also considered to have an anti-peristaltic pace maker.
3) In comparison of lesser and greater curvatures as a main rout of the propaga-tion of action potential, the greater curvature is thought to be more dominant than the lesser curvature.

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Motility of the residual stomach after subdiaphragmatic proximal gastrectomy was observed with cinefluorographic and photo-optical techniques. Subjects studied were twenty patients with benign and malignant lesions of the upper stomach who have undergone proximal gastrectomy in our department. Results obtained are as follows:
In the group of one third resection of the proximal portion of the stomach gastric peristalsis was restored to normal pattern several weeks after operation.
In the group of one half to two third resection gastric peristalsis was inhibited immediately after operation but was markedly restored to normal five to six months after operation.
In the group of three fourth resection with drainage procedure it was rather hard to find restoration of motility of the residual stomach, and esophageal reflux due to duodenal peristalsis was frequently observed. That is to say, it seems that the more extensively proximal portion of the stomach is resected, the more difficult restoration of gastric peristalsis becomes.
From the results mentioned above it is considered that proximal gastrectomy should be performed only in the case being resected less than one half and other pro-cedures such as interposition should be selected in the case for which further extensive resection is necessary.

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