Ten mongrel dogs equipped with four bipolar electrodes and three waterproof strain gauges were used for experiments. In fasting, mean discharge interval of BER of stomach ranged from 10.8 sec. to 13.7 sec., Following feeding, discharge interval of BER showed a considerable prolongation ranging from 13% to 37% dur-ing the initial 60 minutes, and from 4.4% to 23% during the next 9 hour postprandial period. Propagation velocity of BER was almost constant in each animal, however the velocity showed a tendency to decrease slightly following feeding. The velocity in the corpus, antrum and prepyloric area was 0.4 cm/sec., 1.0cm/sec. and 1.5cm/ sec., respectively. Irregegular electrical activities (dysrhythmias) were observed in the antrum most frequently, although their incidence was less than 2% in total dura-tion during the entire observation period. In postprandial period, the contractile activities of the corpus showed a somewhat monotonic pattern with a steady amplitude. The contractile activities of the antrum and the pyloric sphincter showed a waxing and waning pattern with a varying amplitude. Characteristically, the pyloric sphincter showed an intermittent relaxing phase much more frequently as compared with the antrum.

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The four bipolar electrods were chronically sutured on the serosa of pylorus of four female goasts (29-36kg in weight): from oral, electrod No.1, No.2, No.3, No.4.
Electromyograms of abomasum were recorded before and after transection-end-to-end anastomosis of pylorus (between No.2 and No.3 electrods). The results are summarized as follows:
1. Before transection- anastomosis, anti-peristaltic discharge was not found in the pylorus.
2. After the anastomosis, prolonged discharge interval of peristalses and anti-peristalticdischarges occured in the upper part of the anastomosis (No.1 and 2).
3. In the lower part of the anastomosis (No.3 and 4), prolonged discharge interval of peristalses occured in all four goats, but anti-peristalic discharges were found in three goats.
4. Propagation velocity of anti-peristalic discharges became more faster than that of normo-peristalses.

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Alterations in the electrical activity of the stomach were studied in 40 unanes-thetized dogs with intact vagal innervation, with selective proximal vagotomy (SPV) and with truncal vagotomy (TV) using a chronically implanted unipolar needle electrodes.
The basic electrical rhythm (BER) of the normal canine stomach occurred regularly in the frequency of 4.5 to 5.5 cycles per minutes with a waxing and waning of initial and second potentials repeated in every 5 to 6 minutes. After SPV, irregular BER was observed occasionally within a few days postoperatively. After TV, irregularity of BER was more marked and frequent for the first 2 weeks. Subcutaneous administration of bethanechol chloride or histamine decreased the frequency of regular BER and increased the magnitude of second potentials equally in any dog of the control, SPV and TV groups. Similar changes were observed after feeding of the canned meat. Insulin-induced hypoglycemia increased the magnitude of antral second potentials in either control or SPV dogs. In contrast, TV dogs revealed repetition of initial potentials shortly after intravenous administration of insulin, but failed to show any changes relevant to hypoglycemia.

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A photo-optical observation on gallbladder motility was made with the 16 mm cine-cholangiography. The subjects studied were thirty two mongrel dogs. The gallbladder was exposed by a short upper midline abdominal incision under pentothal anesthesia. Gallbladder bile was aspirated and contrast medium was given into the bladder, through a transhepatic route. The cine-cholangiography was done by an image intensifier at a speed of one frame every 2 to 4 seconds. The cinefilms taken were observed repeatedly by the screen projection at various speeds. The drawings were made by tracing the outline of the image of the gallbladder on each frame and were overlapped. Moreover, a contraction curve was made by the cholecystometry using of film motion analyzer in every case. At the same time bile flow into the duodenum was recorded to study a relationship between the gallbladder contraction and motility of the terminal common bile duct.
The results obtained are as follows:
1. In a resting state any contraction of the gallbladder was not seen during 30 minutes, and a peristalsis-like movements of the neck portion was observed. However, there was not a relationship between the contraction curve of the gallbladder and the bile flow into the duodenum.
2. Immediately after giving Caerulein, the contrast medium injected into the gallbladder was rapidly discharged into the common bile duct by a peristalsis-like movement of the neck. The size of the gallbladder was markedly decreased into three fifths of the initial state three minutes after administration. At the same time contrast medium was continuously discharged into the duodenum.
3. After giving pilocarpine a marked contraction with forceful movement of the neck and body was observed, and the size of the gallbladder was decreased into three quarters of the initial state. Bile discharge into the duodenum was markedly increased with an active open- and closing movement of the terminal common bile duct.

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The effects of the stimulants such as antral distention, administration of gastrin and insulin on the gastric motility were investigated in the dogs with innervated antral pouches. The results were as follows:
1. The gastric motility was markedly increased by these stimulants and characteristic motility patterns were recognized in each stimulants.
2. Antral distention stimulated strongly the contraction pressure but not in the frequency of the gastric contractions.
3. Gastrin produced regular and higher frequency contractions and the decrease in contraction pressure of the stomach.
4. Insulin stimulated both of the contraction pressure and the frequency of the gastric contractions.
5. The tests of compound stimulation by each two of these stimuli demonstrated that gastrin constantly produced an increase in frequency and a decrease in cont-raction pressure and that antral distention always increased the contraction pressure of the stomach.

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