Daytime ingestion of alcohol alters nighttime jejunal motility in man.

We studied the effects of acute ingestion of intoxicating doses of alcohol on jejunal motility in six male volunteers ages 24-45 who had two 24-hr ambulatory manometries, one week apart, that each included three standardized meals with either red wine (0.6 g of alcohol/kg) or dealcoholized wine. Breath alcohol was measured at regular intervals for 3 hr following alcohol. The results show that the MMC cycle was significantly (P < 0.01) shorter during the night than during the day in the "nonalcohol" group but not in the "alcohol" group and that the amplitude of contractions was higher during the night than the day in the alcohol group (P < 0.01). All meals interrupted the MMC and induced a fed pattern. After the 300-kcal liquid meal, the duration of the fed pattern was shorter (P < 0.01), with a lower motility index (P < 0.01) and fewer contractions (P < 0.01), than following the two 600-kcal meals. The number of clustered contractions occurring in the postprandial period was lower in the alcohol group than in the nonalcohol group. After the three alcohol doses, a breath alcohol peak was reached in 20-60 min, and in all subjects, breath alcohol fell below 22 micrograms/100 ml after the third hour. This study showed that alcohol had only minor effects on postprandial contractile activity but abolished the circadian variation of the MMC normally seen in healthy subjects. The fact that breath alcohol was low by the time of onset of sleep, suggests that the effects on the MMC may be mediated through central rather than local mechanisms.