Action of endogenous prostaglandins on postprandial pyloric motility: A possible modulation by fats

Abstract

The involvement of endogenous prostaglandins (PGs) and the effect of exogenous PGs on the myoelectrical activity of the pylorus were examined for 6 hours after a meal in dogs chronically fitted with intraparietal electrodes on the gastroduodenal junction. The animals received either a standard meal or a fat meal which consisted of canned food added or not (standard meal) with arachis oil. The cyclooxygenase inhibitors, indomethacin (1 mg/kg) and piroxicam (0.2 mg/kg) given prior a fat meal singificantly increased the frequency of pyloric spike bursts did not modify the pyloric motility associated with a standard meal. Synthetic derivatives of PGE1 (misoprostol, 5–10 μg/kg) or PGE2 (enprostil 0.5–1 μg/kg) reduced the frequency of pyloric contractions after a fat but not a standard meal. It is suggested that both endogenous and exogenous prostaglandins may modulate postprandial pyloric motility when fats are present in sufficient amount into the meal.