Circulating ghrelin levels after food intake during different phases of the migrating motor complex in man.

BACKGROUND

The timing of the migrating motor complexes (MMC) at food intake may influence gastric emptying and release of regulatory hormones. This report studies the relationships between phases I (motor quiescence) and II (intermediate frequency contractions) of MMC and prandial gut hormone response.

MATERIALS AND METHODS

Seven fasting volunteers ingested a meal during phase I or II of MMC verified by manometry, using paracetamol as a marker for gastric emptying. Blood was sampled before, during and 210 min after food intake for analysis of ghrelin, motilin, insulin and paracetamol.

RESULTS

The basal level of ghrelin during phase I was 127.5 +/- 25.4 pmol L(-1) and during phase II was 132.4 +/- 24.8 pmol L(-1). After food intake during phase I, ghrelin fell to 77.2 +/- 10 pmol L(-1); in phase II it fell to 82.7 +/- 17.8 pmol L(-1) within 60 min and returned to baseline levels after 120 min. Baseline levels of motilin were 16 +/- 2 pmol L(-1) and 18 +/- 3 pmol L(-1) during phases I and II, respectively. After food, motilin decreased to 8.5 +/- 0.7 pmol L(-1) and 8.7 +/- 1.0 pmol L(-1) within 60 min and returned to baseline after 90 min. Insulin levels in phases I and II were 8.1 +/- 1.2 mU L(-1) and 8.6 +/- 0.7 mU L(-1), respectively, reaching 138.9 +/- 35.6 mU L(-1) and 167.4 +/- 30.0 mU L(-1) at 45 min postprandially.

CONCLUSIONS

The nutritional status of the gastrointestinal tract at food intake had only a limited impact on plasma ghrelin. After food intake, plasma ghrelin drops, similar to motilin, and resumes preprandial levels within 120 min.