The effects of phentolamine on rabbit basilar artery were studied and compared with those on other smooth muscles.
The drug showed a dose-dependent depressing effect on high-potassium-induced contracture of rabbit basilar artery. The depressing effect was stronger on tonic than onphasic contraction. When phentolamine was applied during high-potassium-induced tonic contraction, dose-dependent relaxation was observed . The degree of phentolamine-induced-relaxation of high -potassium-induced tonic contraction was not affected by surgical denervation of the basilar artery, although catecholamine content was almost completely lost, as indicated by chemical and histochemical experiments . The relaxed tension caused by phentolamine was reversed by addition of Ca in a dose-dependent manner.
Verapamil also showed a dose-dependent relaxing effect on high-potassium-induced contracture, with this relaxed tension being reversed by the addition of Ca in a dose-dependent manner.
The relaxing effect of phentolamine on rabbit basilar artery was stronger than on rabbit aorta or guinea-pig taenia coli.
Phentolamine depressed serotonin- or histamine-induced contraction at a concentration more than 10times higher than the concentration for depression of noradrenaline-induced contraction .
The depression of high-potassium-induced contracture and reversal by additional Ca, especially in denervated preparations, indicates that phentolamine acts directly on smooth muscle in a similar manner to that of Ca antagonists .

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The present experiment was designed to see the effect of anterior or posterior truncal vagotomy on the movement of anterior and posterior walls of the stomach with the use of electrmyography and force transducer.
A total of 28 dogs were prepared with strain gages and bipolar electrodes at both anterior and posterior walls of the stomach. Three types of vagotomy, namely, anterior, posterior and bilateral truncal vagotomy were carried out consecutively or independently. Postoperatively, myoelectrical and contractile activities were compared between the anterior and the posterior wall of the stomach at fasted and fed state .
Results are summarized as follows:
1) Motor activity of the control dogs could be devided into digestive, intermediate interdigestive patterns.
2) Following 3 types of vagotomy, an appearance of the interdigestive pattern showed a tendency of delay which was more evident after the posterior than after the anterior truncal vagotomy.
3) There was little difference in contractile force of the antrum before and after 3 types of vagotomy, except that the hunger contraction was found weaker after all the 3 types of vagotomy. Vagotomy showed little effect on the frequency of basic electrical rhythm at any conditions.
4) In any observation mentioned above, there was no significant difference in the gastric motility between the anterior and posterior wall of the stomach.
In conclusion, the patterns of motor activity were more affected after the posterior after the anterior truncal vagotomy . Little difference in gastric motility, however, was found between the anterior and posterior wall of the stomach after all the 3 types of vagotomy.

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The present study was designed to investigate basic and clinical problems of intraluminal lower esophageal sphincter (LES) manometry. As for the basic study, manometry apparatuses, measuring conditions and methods were revalued. For clinical study, effects of gastric contents and gastrin were studied with special reference to the asymmetry of the LES.
The results obtained may be summarized as follows: Occulusion test performed in a LES model and dogs showed that the rate of pressure increase was greater in proportion to the greater perfusion rate as well as to smaller calibre of the manometry tube. The lower esophageal sphincter pressure (LESP) became greatest when the perfusion rate was increased up to a certin level and also when the withdrawal speed of a manometry tube was slowed down to a certain speed.
Analysis of LES from the point of respiratry reversal disclosed that the pressure was greatest at the direction of 8 o'clock followed by those at 0 and 4 o'clock. The length of LES was longest at 4 o'clock followed by those at 0 and 8 o'clock. These differences in length of LES was mostly in accordance with the length of LES caudal to the point of respiratory reversal.
LESP measured in different postures was greatest in the prone position suggesting the effect of intraabdominal pressure. Intragastric instillation of saline resulted in increase of intragastic pressure and LESP. Asymmetry of the LES in patients with sliding hiatal hernia, esophageal varices and achalasia showed profiles specific to the individual lesion.

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Students of gestation who attempt to explain the maintenance and termination of pregnancy, the mechanism of parturition, and disorders of these processes must not neglect the embarrassing fact that human twins can be born two months apart from the same bicornate uterus.
This simple and direct clinical demonstration that a local factor in the uterus determines the maintenance and termination of pregnancy contradicts all current hypotheses concerning the regulation of myometrial function.

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