In order to study the motor function of the interposed jejunum and the residual stomach following Merendino's operation, three bipolar electrodes were implanted in both the interposed jejunum and the residual stomach using adult mongrel dogs.Three types of surgery;truncal vagotomy (TV), selective proximal vagotomy (SPV) and TV with pyloroplasty (PP) were done in each group of 2 dogs.
In the interposed jejunum, the propagation of the BER was not constantly directed from oral to anal side with phase lead level migration.
In the residual stomach, following TV, the significant reduction of the BER frequency and propagation velocity were noted, and dysrhythmia was observed frequently.
After feeding, however, the BER frequency increased and dysrhythmia was altered to the regular rhythmic pattern, though vomiting episodes were observed frequently.
In the group of TV with PP, the frequency of dysrhythmia was not decreased, but the amount of feeding could be increased.BER frequency and propagation velocity were not changed after feeding.
In the group of SPV, the frequency of dysrhythmia was low, and the propagation velocity was preserved in the normal rate.The vomiting episodes were infrequent.
On pathohistological findings, reflux esophagitis was not observed in all the three types of surgery.
It is concluded that the interposed jejunum protected the esophagus from reflux esophagitis.After TV, PP must be done for the prevention of vomiting episodes.However, after SPV as the residual stomach function is preserved approximately normal, PP can be omited.

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The electrosmyograms of canine external urethral sphincter were recorded and analysed with microcomputer ATAC 450 (Nihon Koden Co.).
Its electromyographic responses to the α-blocker (phentolamine) and β-blocker (propranolol) were not recognzied, although, the action potentials of the external sphincter disappeared by administration of suxamethonium and pancuronium.
The opinions that α-adrenergic system acts dominantly on the external urethral sphincter can not be supported by our data obtained from this study.

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Selective proximal vagotomy (SPV) has been adopted for the treatment of duodenal ulcer, combined with or wihtout drainage operation. This study is aimed to determine whether the drainage operation is necessary or not following SPV, viewed from gastric motility in dogs.
A total of twenty-three mongrel dogs were used, and divided into four experimental groups. They are control, pyloroplasty, SPV, and SPV with pyloroplasty. Electromyographic recordings were made after the fifth post operative day, during the fasted state and after feeding. Results are summarized as follows.
1. The pattern in a frequency change of pacesetter potentials (PPs) was charactaristic in those four groups of animals following three different test meals given, hot milk, cold milk, or solid meals respectively.
2. The difference in numbers of PPs in the body from those in the antrum was carried out from the occurence of antiperistalsis in the antrum. The ratio of PPs in the body and the antrums (AB ratio) was considered useful to depict the gastric activity.
3. Low AB ratio and the wide varience in numbers of antral PPs in pyloroplasty and SPY groups indicated slightly lowered antral activity than in control.
4. SPV with pyloroplasty showed most lowered AB ratio, suggesting the possibility that antral activity was most interrupted in this group.
5. Out of these results and previous reports, the effect of pyloroplasty was discussed viewed from gastric emptying.
Conclusively pyloroplasty should be avoided when SPV is performed for duodenal ulcer, unless pyloric stenosis is present.

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Adenosine triphosphate (ATP) has been known to induce vasodilation in various vascular beds. Recently, we reported that ATP produced vasoconstrictions in isolated internal and external carotid arteries of dogs. In the present study, the mode of the ATP-induced vasoconstriction in the internal carotid artery was analysed from the physiological and pharmacological points of view. The results obtained were as follows: 1) ATP (5×10^-6-2×10^-4M) caused dose-dependent vasoconstrictions in the internal carotid artery. 2) The ATP-induced vasoconstriction was not affected by pretreatment with phenoxybenzamine, propranolol, atropine, cyproheptadine, or tetrodotoxin. 3) Verapamil suppressed dose-dependently the contractile response. 4) ATP caused no vasoconstriction in a calcium-free Krebs solution containing 1mM EGTA. 5) ATP produced no further vasoconstriction in the preparation which had been in a state of contracture in a high potassium Krebs solution. These results suggest that an increase of potential-dependent Ca⁺⁺ influx into the arterial smooth muscle cells may play a major role in the ATP-induced vasoconstriction.

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