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Effect of transection and pacing on human jejunal pacesetter potentials
Gastroenterology
|December 1, 1986
Summary
Surgical transection slightly slows human jejunal pacesetter potentials (PPs) frequency. Electrical pacing did not effectively alter PPs in either intact or transected jejunum.
Area of Science:
- Gastroenterology
- Physiology
- Surgical Science
Background:
- The human jejunum exhibits intrinsic electrical activity, known as pacesetter potentials (PPs), which regulate motility.
- Understanding how surgical alterations, like transection, affect jejunal electrical activity is crucial for gastrointestinal function.
- Electrical pacing is a potential therapeutic strategy for motility disorders, but its efficacy in the jejunum requires investigation.
Purpose of the Study:
- To investigate the impact of surgical jejunal transection on the frequency of human jejunal pacesetter potentials (PPs).
- To assess the effectiveness of electrical pacing in altering jejunal PPs frequency in both intact and transected jejunum.
Main Methods:
- Implantation of temporary bipolar electrodes on the jejunal seromuscularis in patients undergoing Roux gastrectomy (transected group) and control patients.
- Recording of jejunal PPs frequency proximal and distal to the transection site in Roux patients, and at similar sites in controls.
- Application of electrical pacing (15 mA, 50 ms pulses at 0.2-1.0 cpm faster than native PPs) to assess entrainment.
Main Results:
- Jejunal PPs frequency was slightly reduced distal to the transection in Roux patients (11.0 cpm) compared to proximal to the transection (11.3 cpm, p<0.05).
- Control patients without transection showed identical PPs frequency in both proximal and distal jejunal segments (12.0 cpm).
- Electrical pacing successfully increased jejunal PPs frequency in only one of nine tested patients, indicating limited entrainment.
Conclusions:
- Surgical transection of the jejunum causes a minor decrease in pacesetter potentials frequency.
- Electrical pacing is not readily effective in entraining jejunal pacesetter potentials in either intact or surgically altered jejunum.
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