The effects of daikenchuto (DKT) on propulsive motility in the colon.
BACKGROUND
The purpose of this study is to examine the use of daikenchuto (DKT), a traditional Japanese medicine, as a potential treatment for opiate-induced slowing of intestinal transit in an isolated guinea pig colon model of motility.


METHODS
Isolated segments of distal guinea pig colon were mounted in a perfusion chamber and imaged with a digital video camera interfaced with a computer. Fecal pellets were inserted into the oral end of the colonic segment and the rates of propulsive motility over a 3 to 4 cm segment of colon were determined in the presence and absence of test compounds. In addition, intracellular recordings were obtained from intact circular muscle, and the responsiveness of inhibitory and excitatory junction potentials to DKT was evaluated.


RESULTS
The addition of D-Ala2, N-Me-Phe4, Gly-ol5 (DAMGO), a selective μ-receptor agonist, caused a concentration dependent decrease in colon motility. Naloxone did not affect basal activity, but partially restored motility in the DAMGO treated preparations. DKT (1 × 10(-4)-3 × 10(-4)g/mL) also reversed the inhibitory effect of DAMGO treated colon in a concentration dependent manner. At higher concentrations (1 × 10(-3)-3 × 10(-3)g/mL), however, this effect was lost. Motility slowed even further when naloxone and DKT were combined with noticeable disruptions in spatiotemporal patterns. Interestingly, when added alone, DKT resulted in reverse peristalsis of the pellet. In electrophysiologic studies DKT inhibited both excitatory and inhibitory junction potentials.


CONCLUSIONS
DKT appears to be as effective as naloxone in restoring motility in DAMGO treated colon. These two agents, however, do not appear to have an additive effect. When used on untreated colon segments, DKT appears to cause disruptions in the intrinsic reflex circuit of the gut resulting in a disruption of neuromuscular communication.
Wood
Michael J
MJ
Department of Surgery, University of Vermont College of Medicine, Burlington, Vermont 05401, USA. michael.wood@vtmednet.org
Hyman
Neil H
NH
Mawe
Gary M
GM
D000701:Analgesics, Opioid / Q000494:pharmacology; D000818:Animals; D003106:Colon / Q000187:drug effects* / Q000502:physiology*; D004347:Drug Interactions; D004594:Electrophysiology; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)- / Q000494:pharmacology; D005260:Female; D005769:Gastrointestinal Motility / Q000187:drug effects* / Q000502:physiology*; D006168:Guinea Pigs; D008297:Male; D020835:Medicine, Kampo; D009119:Muscle Contraction / Q000187:drug effects / Q000502:physiology; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology; D009270:Naloxone / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D005894:Panax; D010936:Plant Extracts / Q000494:pharmacology*; D032106:Zanthoxylum; D030521:Zingiberaceae
D000701:Analgesics, Opioid; D009292:Narcotic Antagonists; D010936:Plant Extracts; C121414:dai-kenchu-to; D020875:Enkephalin, Ala(2)-MePhe(4)-Gly(5)-; D009270:Naloxone