The failure of truncal vagotomy to affect motilin release in dogs.

To elucidate the relationship between vagus nerve and motilin release, we have studied the influence of truncal vagotomy with pyloroplasty (TV) on motilin release in the fasting state and for 120 min following an intraduodenal administration of 10 g glucose in a 50-ml water solution or 5 g soybean oil. TV did not influence the intermittent fluctuation or concentration of plasma motilin in the fasting state. Intraduodenal glucose administration inhibited motilin release, but this was not affected by TV. Intraduodenal fat administration accelerated motilin release, but this effect also was not affected by TV. These results suggest that motilin secretion in the fasting state and after nutrient ingestion is not influenced by TV.