EFFECTS OF TRUNCAL VAGOTOMY ON SERUM MOTILIN LEVELS, GASTRIC MOTILITY PATTERNS AND GASTRIC EMPTYING: AN EXPERIMENTAL STUDY

Using adult mongrel dogs, gastroduodenal motility, gastric emptying and pertinent serum motilin levels were measured under concious states before and after transthoracic truncal vagotomy. Gastroduodenal motility was recorded by chronically planted strain gage transducers along the gastrointestinal tract. Gastric emptyings were measured by x-ray examinations after barium-meat-meal ingestions or by gastric contents sampling method through the total pouch cannula after normal dog food ingestions. Results were as follows; 1. Gastric motility patterns recorded by strain gage transducers were classified into two patterns that were a digestive pattern (D.P.) and an interdigestive pattern (I.P.). Serum motilin levels were elevated during high-amplitude contractions and lowered during resting phase of interdigestive periods. 2. After vagotomy, strengs (hights) of antral contractions and phasic changes were decreased with the lack of I.P. These postvagotomy changes were thought to be related with the delayed gastric emtying after vagotomy. Gastric lavation through the cannula or pyloroplasty produced no effect on recovery of I.P. This fact suggested that the lack of I.P. was the direct effect of vagotomy and not due to delayed gastric contents emptying. 3. On the assumption that motilin had the major role on the regulation of I.P., vagotomy seemed to produce an effect to prevent phasic motilin release.