Differences of discharge patterns in various vagal afferent fibers from gastric wall were studied to assess the accuracy of the transformation of the applied stimulation into afferent discharge.
The right vagus nerve (partly left) was divided at the peripheral end of Ggl. nodosum and afferent impulses from gastric wall were recorded in the functionally isolated single units.
In the vagus, the most effective source of afferent activity was the area extending from the lesser curvature to the posterior wall of antrum, only rarely was stimulation at the other parts effective. The discharges of 23 single units isolated from the vagus nerve were classified to three types as follows.
(1) The discharges corresponded with the change in gastric volume and gastric peristalsis, were recorded in the nerve from antrum (including lesser curvature) and seemed to carry the information of tension change.
(2) The discharges corresponded with the change in gastric volume and not gastric peristalsis, were recorded in the nerve from cardiac portion and seemed to carry the information of stretch change.
(3) The discharges, in the form of transient brief burst, occurred immediately after the increase of the gastric volume but disappeared soon, responded neither to the constant holding of air volume in the stomach nor to frequently occurring gastric peristalsis. Furthermore, this type of fibers carried tonic discharges and the discharge frequencies increased in accordance with the increase in the acidity of insufflated HCl acid.
The τ-S relations in the discharges of the second type suggested that the firing patterns were quite stable to the applied stimulation.

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In canine stomach, a mucosal septum was made at the boundary between the corpus and antrum with a balloon placed inside of the antral portion. By inflating the air, intraballoon pressure was raised to 30 and 40 cmH₂O and the changes in antral motor function was studied before and after vagotomy with the use of electromyography. The results are summarized as follows.
1. Reaction to antral distension stimuli was compared before and after vagotomy.Findings after vagotomy were, in general, prolongation of discharge intervals, acceleration of propagation velocity and increased incidence of antiperistalsis with these indicating the less sensitivity to the stimuli of pressure increase.
2. Relationship between the intra-balloon pressure and the amount of air needed to inflate the balloon was as follows. After vagotomy, an increased amount of air was needed to obtain the same intra-balloon pressure suggesting the reduction in tonus of the gastric wall.
The present study has revealed that the vagotomy reduces the motor function of the antral portion, tonus of the gastric wall and responses to the antral distension stimuli. Based on these findings, it is postulated that the vagotomy inhibits motor function of the antral portion.

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Pharmacological and histochemical observations were made on the innervation of the guinea-pig trachea. Field stimulation with A .C.(2 V/cm, 50 Hz) elicited a biphasic response of the tracheal smooth muscle consisted of initial contraction followed by relaxation. This biphasic response was susceptible to the blockade of tetrodotoxin (10^-8g/ml), which may imply the involvement of nervous elements in this response. The contractile component of the biphasic response was greatly reduced by atropine (10^-7g/ml), and the relaxant component was reduced by bretylium (10^-5g/ml). Furthermore, transmural stimulation (1 msec, 1-50 Hz) elicited contraction or relaxation of the trachea. The contraction was easily reversed to relaxation by atropine (10^-7g/ml), and the relaxation was entirely abolished by bretylium (10^-5g/ml). These results may suggest the presence of excitatory cholinergic and inhibitory adrenergic nerve fibers in this tissue. Histochemical observation, at the same time, revealed the presence of adrenergic and cholinergic nerve fibers within the musculature of the trachea.

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The present study was made to investigate the details of defecation mechanism. The subjects studied were forteen patients who did not suffer from intestinal diseases. For this purpose, 16 mm X ray cinematogram was taken on every patient using barium enema in supine position. A photo-optical measurement was performed on these cinefilms by the use of a film motion analzyer. The results obtained are as follows:
1. The distension of the rectal ampulla by increasing the internal pressure was one of the factors giving rise to awareness of the need to evacuate the rectum.
2. In the left side colon and rectum, obvious movement was not observed before defecation took place. The colon and rectum went down as a whole toward the pelvic space at the time when defecation started. When distension at the ampulla by intraabdominal pressure exceeded the tension of the anal sphincter, defecation started.
3. The transportation of feces in the left side colon was observed during defecation. The main function of the left side colon seems to be storage of feces.

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