Effects of Loperamide on the motility of the isolated intestine in guinea-pigs, puppies and rats were examined.
The spontaneous contractions of the small intestine and colon in puppies were inhibited at relatively high concentration of the agent (10^-5 g/m1). The peristaltic reflex in the guinea-pig ileum was slightly inhibited at concentrations of 10_-8 to 10_-7 g/ml, and was completely abolished at 10_-6 g/ml. The agent (2×10^-7 g/ml) inhibited the longitudinal contraction of the guinea-pig ileum elicited by transmural electric stimulation. The agent (10^-5 g/ml) inhibite the acetylcholine-induced contraction of the colon and small intestine in puppies and induced the hyperpolarization of the membrane potential and the abolition of spike potentials of the intestinal muscle in rats.

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15 adult dogs fasted over night were used under Ketalar anesthesia. Experi-ment were undertaken during 3 months on 3 groups of animals vagotomized, splanchnicotomized and transected both extrinsic nerves. The intragastric pressure was measured by balloon-strain gauge method. The intragastricpressurewa elevated in a way of filling with 200 ml of Ringer's solution within 1 minute every 2 minutes till a total of 800 ml.
Following results were obtained
1) The intragastric pressure at the initial period of gastric fullness and the average intragastric pressure during 2 minutes after filling of Ringer's solution in 3 groups were maintained in a higher level compared to that of the control dog at every time after operation and every stage of gastric fullness. Their pressure gradients were shown sharp slopes compared to that of the control dogs.
2) The amplitude of the peristaltic movements in 3 groups was larger than that of the control dogs at every time after operation and every stage of gastricfullness.
3) The results in the chronic experiments were almost the same with that in the acute experiments of the present author (Ikeda, 1976 a b).

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Antireflux effect of various operations for achalasia of the esophagus was investigated with the use of the manometric study. Operative procedures subjected to the present comparative study were proximal gastrectomy with end-to-end esophagogastrostomy, Wendel procedure, Heller procedure and Fundic patch operation, each prepared in four mongrel dogs. Incidence of postoperative reflux with possible esophagitis was greatest in proximal gastrectomy followed by Wendel and Heller procedure. Fundic patch operation well prevented the reflux with greater values of pressure as well as dimension of the lower esophageal sphincter than those of the control series.
In other series of experiment in dogs, an attempt was made to reveal the rationale of the effective valvular mechanism of the Fundic patch operation preparing various sizes of the valve. When compared by the manometric study, Fundic patch procedure with an incision of 6 cm in length, formation of the artifiical mucosal valve and two thirds enclosure of the distal esophagus with the fundus like fundoplication sufficiently prevented the reflux. Preparation of the valve smaller in size accelerated the incidence of postoperative reflux.

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With the use of gastroesophageal withdrawal pH curve, pathophysiology after various surgical procedures for achalasia of the esophagus was investigated experi-mentally from the view point of postoperative reflux. A total of 68 dogs were divided into four groups and were prepared with proximal gastrectomy with end-to-end esophagogastrostomy, Wendel procedure, Heller procedure and Fundic patch opera-tion, respectively. In the group with Fundic patch operation, efficacy of the flap valve, mucosal valve and fundoplication was also evaluated preparing them in various sizes.
The results obtained may be summarized as follows:
1) Withdrawal pH measurement is a sentive mean to detect the gastroesophageal reflux.
2) Proximal gastrectomy with end-to-end esophagogastrostomy and Wendel procedure yielded worst results with severe gastroesophageal reflux. On the contrary, Fundic patch operation best controlled the gastroesophageal reflux.
3) Gastroesophageal reflux could be prevented by the Fundic patch operation with the flap valve 6 cm in length and fundoplication enclosing around 1/2 to 2/3 circumference of the distal esophagus.

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Endoscopic gastroelectromyograms were obtained from 8 patients with gastric cancer, which was located at the gastric antrum. These cancers include 6 cases of advanced cancers and 2 cases of early cancers with mucosal invasion. On healthy volunteers, the gastroelectromyograms from the gastric antrum showed spike bursts with equal intervals. On the other hand, in the patients with advanced cancers on which muscular layer was completely destroyed by the cancerous invasion, the gastroelectromyograms from the cancerous lesion showed no spike bursts. However, in the patients with mucosal cancers in which the cancerous invasion destroyed neither muscular membrane nor muscular layer, the gastroelectromyogram from the cancerous lesion showed spike bursts similar to those of healthy volunteers.
From these results, it is proved that the deeper cancerous invasion disturbed the local motility at the cancerous lesion. In future, endoscopic lead of gastro-electromyogram will become useful for the diagnosis of the degree of cancerous invas-ion and infiltration.

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