[An electromyographic study of effects of pyloroplasty on gastric motility following selective proximal vagotomy in dogs (author's transl)].

Selective proximal vagotomy (SPV) has been adopted for the treatment of duodenal ulcer, combined with or without 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 characteristic 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 occurrence 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 variance in numbers of antral PPs in pyloroplasty and SPV 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.