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Updated: Aug 12, 2026

Gastrointestinal Motility Monitor (GIMM)
Published on: December 1, 2010
[Thio- and oxybarbiturates inhibit peristalsis in the Guinea-pig ileum in vitro]
M K Herbert1, W Berg, A Kublik
1Klinik für Anaesthesiologie der Universität Würzburg. mherbert@anaesthesie.uni-wuerzburg.de
Introduction:
Inhibition of gastrointestinal motility by drugs used for anaesthesia or sedation in critically ill patients in the ICU is a major problem leading to various complications. Thus this study examines whether the thio- and oxybarbiturates thiopentone and pentobarbitone exert an inhibitory effect on intestinal peristalsis.
Methods:
Peristalsis in isolated segments of the guinea-pig small intestine was elicited by distension of the gut wall through a rise of intraluminal pressure and recorded via the intraluminal pressure changes associated with the aborally moving peristaltic contractions. Thiopentone and pentobarbitone (0.1 - 300 microM)-induced inhibition of peristalsis was reflected by an increase of the peristaltic pressure threshold (PPT).
Results:
Thiopentone (EC50 = 19,8 microM) and pentobarbitone (EC50 = 99.7 micro M) concentration-dependently increased the PPT. While the vehicle (saline) and 0.1 - 10 micro M thiopentone and pentobarbitone were without any effect on the PPT, 100 micro M caused a significant increase in PPT, and complete abolition of peristalsis occurred after 300 micro M thiopentone or pentobarbitone in all segments tested. Inhibition was reversed by changing the bath solution.
Conclusions:
Thio- and oxybarbiturates inhibit intestinal peristalsis in the guinea-pig ileum. It is assumed that thiopentone and pentobarbitone affect propulsive peristalsis also in the human small intestine.
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