In order to investigate the correlation between the cortical function and the motility of bowels, the responses of the action potentials in bowels to the cutting or stimulation of several cortical areas were observed.
Rabbits were anesthetized with urethane. In some of them, the rostral portions of diencephalons were cut and in the others, electrical or chemical (1-glutamate) stimuli were given to the following cortical areas which seem to be closely correlated with the autonomic nervous system; prefrontal area, gyrus cinguli anterior, gyrus cinguli posterior and hypocampus. The action potentials were recorded from the serous membrane sides of duodenum and ileum by means of bipolar metal electrodes. The results obtained were as follows:
1. By cutting off the rostral portions of diencephalons, the increase in amplitude of action potential, the appearance of large spikes (200μV or more) and the prolongation of the duration of the burst were observed.
2. By stimulation of the prefrontal area, gyrus cinguli anterior and hypocampus, spike potentials increased its amplitude and prolonged its duration. On the other hand, stimulation of gyrus cinguli posterior depressed the action potential.
3. After cutting off the vagi at the level of the neck, stimulation of cortical areas was ineffective to produce the remarkable change in action potentials of bowels.

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By recording the electrogram and mechanogram of the ureter simultaneously, the relationship between the configuration of action potential and contraction was studied.
The action potential of the guinea pig's ureter consists of two components, the slow potential and the oscillating spike potential. Tetraethylam-monium (TEA) ion diminished the spike component without affecting the slow component. In this case, the slow potentials appeared repetitively and spontaneously, each of them was accompanied by contraction and the evident summation of contraction could be observed. The contraction of TEA-ureter was of tetanic nature.
When NaCl in Krebs solution was substituted by choline chloride, the action potential lost its slow component and there occurred the repetitive burst of grouped spike potentials. The single spike potential evoked the single weak contraction. In each burst, the summation of contraction was recorded. The contraction of choline-ureter was also of tetanic nature.
The effect of oxytocin upon the ureter was similar to that of Ca ion deficient environment. By the administration of oxytocin in the soaking fluid, the action potential lost its spike component but the slow component remained unaffected. In this case, however, with the decrease in size of the spike potential, the contraction became weaker and finally disappeared. The disappearance of contraction by oxytocin is due to the disturbance or block of the excitation-contraction coupling.
From the facts mentioned above, it could be concluded that both slow and spike components in action potential of the guinea pig's ureter held the ability to evoke the contraction, as far as the excitation-contraction coupling was not disturbed.

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The responses of the stomach movements to the stimulation of the pons were investigated in the anesthetized and non-anesthetized dogs. The stimulated areas were determined by the histological examination.
1) A hundred and fourteen motor and 78 inhibitory responses were obtained. The motor responses were obtained not only through the vagus nerves, but also through the splanchnic nerves. The inhibitory responses were obtained not only through the splanchnic nerves, but also through the vagus nerves.
2) Both the motor and inhibitory effects were obtained in the same area, that is, the Formatio reticularis, Tr. vestibulospinalis, Nucl. vestibularis medialis, Tr. rubrospinalis, Fasc. longitudinalis medialis, Nucl. cuneatus, Pedunculus cerebellaris superior, Tr. spinalis n. trigemini, Lemniscus lateralis were responsible for the both reactions. Especially, the Tr. rubrospinalis and Nucl. & Tr. n. trigemini were responsible for the motor effects, and the Tr. vestibulospinalis was responsible for the inhibitory effects. The reversed responses of the stomach did not depend on the stimulating conditions or on the anesthetization or non-anesthetization of the dogs.
3) The stimulation of extrapyramidal tracts, such as the Ped. cerebellaris sup., Tr. vestibulospinalis, Tr. rubrospinalis, Nucl. vestibularis lat., -inf., Fasc. longitudinalis med., Tr. tectomedullaris, Nucl. olivaris sup.caused the motor and inhibitory responses of the stomach.
4) The stimulation of the cerebellar pedunculus produced both responses of the stomach.
5) The stimulation of the somatic nerves and its nucleus (Nucl. motorius n. trigemini, Nucl. n. abducens, Genu n. facialis) also produced the both responses.

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The smooth muscle layer of cat nictitating membrane was fixed in permanganate, embedded in epon and observed with electronmicroscope. The smooth muscle cells are enclosed with basement membrane, except where the specialized cell membrane interconnection (intrusion body) is present. This intrusion body is frequently observed in the areas where nerve elements are sparse. Fused membrane or quintuple layered system can not be observed.
The unmyelinated nerve endings are distributed among the smooth muscle cells. In the wide extracellular spaces where the nervous elements are rather scant, naked axons are found with basement membrane. But when the nerve terminals are abundant, naked axons keep often intimate relationship with the muscle cells. They are either contact directly with the muscle cells without basement membrane or embedded deep in muscle cells.
Occasionally, the smooth muscle cell membrane at the point of contact with the nerve ending shows the presence of endoplasmic reticulum and pinocytotic vesicles. The closest apposition of the axon and the muscle cell is about 80 Å. At these contact points, the specialized structure such as secondary synaptic cleft seen in skeletal muscle is not clear. The synaptio vesicles in the axon are divided into two types following their average diameters of 500 Å and 800 Å. The smaller vesicles with 500 Å diameter could further be classified into the granular and agranular types, and they are often found in the same axon. The functional differentiation of them is impossible at present.

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The present investigation was undertaken in order to elucidate the effects of vitamin D on the uterine motility and interrelationship between vitamin D and ovarian hormones.
Uterine motility was recorded kymographically in conscious animals with the help of small balloon inserted through the fistulae.
The results obtained are as follows:
1) A single intramuscular injection of vitamin D of 10, 000 or 50, 000 i.u. per kg body weight caused an increase in the uterine motility lasting 3 to 4 days, and then gradually was brought to its inhibition.
2) Daily intramuscular administration of 5, 000 or 10, 000 i.u./kg for about 40 days caused an increase in the uterine motility for about first 2 weeks and later the motility was gradually suppressed. When, 50, 000 i.u./kg was given daily, uterine activity was strongly inhibited from the beginning.
3) When vitamin D and estrogen were administered simultaneously, the increase in the frequency and amplitude of uterine contractions was observed. This seems that vitamin D has a synergetic action to estrogen.
4) The administration of progesterone with vitamin D caused an inhibition of the uterine motility in the beginning, but this inhibitory effect disappeared gradually with the prolongation of the period of administration. This suggests the antagonistic action of vitamin D against progesterone.
5) The senstivity of the uterine motility for oxytocin well correlated with the promoting action of vitamin D.

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An electromyographic study of the influence of six refined amines (histamine, acetylcholine, tyramine, putrescine, cadaverine and isoamylamine) on the movement of the gastrointestinal tract was carried out in 60 rabbits to evaluate the biological toxicity of these amines in cancer.
Of these six amines, four amines except acetylcholine and tyramine were proved paper-chromatographically in cancerous tissue of the stomach by the author's colleagues, Tsushima et al.
The following conclusions were made out of the results obtained:
Histamine and acetylcholine slightly accelerate the peristaltic movement of the gastrointestinal tract, while the remaining amines have no effect under intraluminal administration in the amount of 0.3mg/kg.
Each of the refined amines markedly accelerate peristalsis by dripping them in 0.5% solution on the serosal sites locally and also by administrating them 0.3mg/kg into the regional arteries.
Intravenous administration of these amines shows no effect on the peristaltic movement in the group of rabbits with normal liver function, but accelerates markedly in the group of rabbits in which hepatic dysfuction is induced by carbon tetrachloride.
The accelerating effect of these amines on the peristaltic movement is more predominant in the distal portion of the gastrointestinal tract than in the proximal portion.

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Direct visualization of the gastric acid secretion as well as pH determination were carried out under several vagal preparations accompanied by maximum histamine stimulation.
Under Nembutal anesthesia, canine stomach was opened along the greater curvature and the entire gastric mucosa was exposed for the direct observation of the gastric acid secretion which was possible by applying Congo red-Carbowax on the gastric mucosa.
The results obtained are summarized as follows:
1. Unilateral vagotomy at the height of the neck resulted in the decrease in the acid secretory areas on both anterior and posterior walls of the stomach, which was later enhanced by bilateral vagotomy. Vagotomy also decreased an acidity of the gastric juice.
2. Severance of vagi was attempted supradiaphragmatically and subdiaphragmatically as well. Section of the anterior branch showed an inclination in the reduction of an acid secretory area mostly of the anterior wall, and section of the posterior branch resulted in vice versa. This inclination of limited and partial reduction in the acid secretory area of the gastric mucosa was more predominant in the dogs where the vagus or vagi were severed subdiaphragmatically. Section of the vagus at these levels also reduced an acidity of the gastric juice.
3. Out of the results described above, it was shown that the decrease in the acid secretory area well correlated with the vagally denervated area of the gastric mucosa traced anatomically from the site of vagotmy.
4. In the reduction of an acid secretory area induced by vagotomy, it was of some interest to notice that the acid secretory area tended to localize to the corpus mucosa adjacent to the antral border. Histologically, this area well coincides with the richly distributed area of the parietal cells.

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