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Tonic and phasic pyloric activity in response to CCK-octapeptide
Frank K Friedenberg1, Joshua Desipio, Annapurna Korimilli
1Department of Medicine, Section of Gastroenterology, Temple University Hospital, Temple University School of Medicine, 3401 N. Broad Street, Philadelphia, PA 19140, USA. frank.friedenberg@temple.edu
Digestive Diseases and Sciences
|February 14, 2008
Summary
Cholecystokinin-octapeptide (CCK-octapeptide) stimulates pyloric sphincter activity, increasing antral pressure and causing tonic and phasic contractions. Higher CCK-octapeptide doses yield a greater contractile response.
Area of Science:
- Gastroenterology
- Physiology
- Pharmacology
Background:
- Gastric motility and pyloric sphincter function are crucial for digestion.
- Cholecystokinin-octapeptide (CCK-octapeptide) is a key regulator of gastrointestinal processes.
Purpose of the Study:
- To evaluate the efficacy of a high-resolution solid-state catheter system in measuring regional pressure changes.
- To assess the effects of CCK-octapeptide on antral and pyloric pressures.
Main Methods:
- Seven subjects received a 30-minute infusion of CCK-octapeptide at doses of 0.02 or 0.06 microg kg(-1) h(-1).
- Regional pressures in the antrum and pylorus were monitored using a high-resolution solid-state catheter system.
Main Results:
- CCK-octapeptide infusion significantly increased mean antral pressure during phase I migrating motor complex (MMC).
- The 0.06 microg kg(-1) h(-1) dose of CCK-octapeptide elevated tonic pyloric pressure, unlike the lower dose.
- Pyloric phasic pressure waves exhibited a peak pressure of 153 +/- 28.4 mmHg at a frequency of 4.9 +/- 1.1 contractions min(-1).
Conclusions:
- CCK-octapeptide induces both tonic and phasic activity in the pyloric sphincter.
- A higher dose of CCK-octapeptide (0.06 microg kg(-1) h(-1)) elicits a more pronounced contractile response compared to a lower dose (0.02 microg kg(-1) h(-1)).
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