The effects of new antispasmodic drug, 2, 4, 6-trihydroxypropiophenone (THPP) on the motility of bile duct, ureter and the colon were examined.
1) Spontaneous contraction of the isolated bile duct was inhibited and tonus was markedly decreased by the administration of THPP at doses greater than 8×10^-5 g/ml. To provoke this spasmolytic effect on the isolated ureter a dose of 4×10^-4 g/ml was necessary.
2) Spasms provoked by acetylcholine, BaCl₂ and serotonin were inhibited by THPP. Antispasmodic action of THPP against the evoked spasm by serotonin was stronger than that against the spasm by acetylcholine or BaCl₂.
3) The ureter and the bile duct were perfused with Ringer-Krebs solution and the amount of outflow was measured. The outflow from ureter periodically decreased at the automatic contraction. The outflow of ureter and that of bile duct decreased at the appiciation of acetylcholine, BaCl2 or serotonin. because of the increase in muscle tonus. But when THPP was given the outflow increased because of its antispasmodic action. 4) The frequency of automatic contractions of the isolated ureter was the greatest at the inner pressure of 20 cm H₂O. But in case of the bile duct the inner pressure was 14 cm H₂O.

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In the past, extraluminal leading of the gastric action potentials had been used experimentally and clinically with satisfactory results, while intraluminal leading had been attempted only by a few researchers because of technical difficulty and the electromyograms obtained with this method were not entirely satisfactory.
A new suction needle electrode was devised by us to lead the gastric action potentials intraluminally. Electromyograms of the stomach from 10 human beings and 10 dogs led with this electrode proved to be quite similar to those led with the the needle electrode from the serosal aspect of the stomach.
With this method, constant and satisfactory electromyograms may be recorded from the mucosal aspect of the stomach, thus eliminating general anesthesia and laparotomy. Easier and wider use of electromygoraphy of the stomach in the clincial as well as research field is expected.

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For the purpose of understanding the contractile mechanism of the uterine smooth muscle, actomyosin-ATPase activity of crude extracts of the rat uterus was investigated under various experimental conditions including influences of inorganic ions.
The enzyme activity was more or less altered in the absence of anterior pituitary, adrenal or overy. However, it resumed the level prior to the operation following subsequent treatment with ACTH, desoxycorticosterone and estrogen respectively.
The role of the adrenal seemed to be of interest, especially in the fact that desoxycorticosterone was fairly effective, but not hydrocortisone for recovery of the enzyme activity, if given after the removal of the adrenal. This suggests the importance of electrolytes on the enzymatic activity. From this fact, in bioassay of adrenal contex extract, the survival tes of adrenalectomzied rat might be replaced with the method to determine the actomyosin-ATPase activity of the uterine muscle.
It is conceivable thatcontraction and relaxation of the uterus during the period of gestation and parturition could be more or less explained in relation to the actomyosin-ATPase activity, if the conditions required were thoroughly realzied.
From the results above mentioned at least endocrine glands such as anterior pituitary, adrenal and ovary might be considered to have intimate relation to th enzyme activity concerned.

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The relationship between ATP-ase activity and the superprecipitation of actomyosin which was extracted from the rat's uterine muscle was investigated. Results were as follows:
1) The superprecipitation occurred in the wide range of KCI concentration, 0.05-0.20 M, and particularly strongly in the range of 0.08-0.12 M.
2) In this range of KCl concentration, actomyosin-ATP ase activities were nearly the same degree.
3) In regard to the effects of inorganic ions upon AM, the experiments indicated that the cooperation of Ca and Mg ions is required for the contraction of AM system. Moreover, Mg ion activated AM ATP ase activity.
4) The relationship between ATPase activity and superprecipitation. of AM was almost parallel.

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1. In the denervated cervical esophagus of the hen, mechanical or chemical stimulation of its mucosa produced the rhythmic contractions at both sides of the stimulated spot. After intravenous administration of C₆, atropine or tetrodotoxin the response was almost absolished. It may be concluded that the excitatory effect is due to the mucosal intrinsic reflex via the ganglion cells of Auerbach's plexus in the esophagus.
2. In the innervated cervical esophagus of the hen, distention of the esophagus produced the rhythmic contraction of the esophagus oral to the distended spot, while the esophageal motility anal to it was inhibited and immediately after cessation of the distention the rhythmic powerful contractions were elicited. It may be supposed that the afferent impulses of the esophageal nerves and the esophageal branches of the vagus nerve elicited by the distention excite the activity of the esophageal motor center (the cranial center) which innervates the esophagus oral to the stimulated spot, while they inhibit that of the center (the caudal center) which innervates the esophagus anal to it, and that the cranial center has an ability successively to excite the ganglion cells of the caudal center.

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The present study deals with the effect of local distension of the stomach on the motor function of the pyloric portion. The experiment was undertaken with canine stomachs. A. rubber balloon was introduced into the stomach. And, by inflating the balloon with air. fnn.dus, body and pyloric region of the stomach was distended individually. The results are summarized as follows:
1) When the same amount of air was introduced, excitation of the pyloric portion was most evident by the distension of pyloric region followed by the distension of the body and the fundus.
2) Gradual over-distension of any region of the stomach resulted in excitation of the peristaltic movement which was most remarkable in the pyloric region associated with frequent occurrence of anti-peristalsis.
These findings suggest that the abnormal excitation of the pyloric portion may be caused by severe gastric retention followed by an increase in intraluminal pressure of the stomach, particularly of the pyloric portion.

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The spontaneous and oxytocin induced electrical activity of the pregnant uterus of rat has been studied in vivo by recording electromygorams at various stages during pregnancy. The electrical activity has been compared at different uterine portions in the pregnant uterus of rat; at the myometrium of the corpus, the cervix, the edge of the placental area, and the placental area. Also, one or two electrodes (silver wire, 50μ in diameter) were introduced into the myometrial coat at the different uterine poitions for the recording as described in the previous report. The experiments were performed on the 12th, 13th, 14th, 18th and 21st days of pregnancy. The electrical activity of the pregnant rat uterus consisted of repetitive spike discharges at the different uterine portions through various stages of pregnancy. In vivo, myometrium of the placental area showed a little spontaneous activity before term, but there was no difference between the myometrium of the edge of the placental area and of the other portions (the corpus and the cervix). No distinction between the electrical excitability of placental and nonplacental myometrium was observed at term. After the above control records were taken, oxytocin was injected in a dose of 2 or 3 i.u. intraumuscularly and the response in increase of spike discharges at the different uterine portions were clearly detected.

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Effects of Metoclopramide on the isolated intestine of guinea-pig were studied. The results obtained were as follows:
1) Metoclopramide usually produced a stimulating action on each preparation of the isolated jejunum, ileum and colon of guinea-pig.
2) Maximum tension was observed at the concentrations of Metoclopramide (10^-5-10^-4 g/ml) on the isolated guinea-pig colon.
3) The stimulating action of Metoclopramide was not observed on KCl-depolarized preparation of the isolated guinea-pig colon.
4) Atropine (10^-5 g/ml) did not block the stimulating action of Metoclopramide on the isolated guinea-pig colon.
5) The stimulating action of Metoclopramide on the isolated guinea-pig colon was blocked by hexamethonium (2.5±10^-3 g/ml), tetrodotoxin (10^-6g/ml) and the treatment of botulinum toxin (type C, 10⁵ mouse LD₅₀/ml, 15 min.).
6) High concentration of Metoclopramide (1.5±10^-4 g/ml) blocked the nicotine contraction.
From these results, it was suggested that Metoclopramide had a stimulating action on the isolated intestine of guinea-pig not through the muscle membrane, but through the intrinsic nerve. Furthermore, it would be considered that high concentration of Metoclopramide had an inhibitory action.

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