Effects and mechanisms of electroacupuncture on glucagon-induced small intestinal hypomotility in dogs.
BACKGROUND
Little is known on the effect of electroacupuncture (EA) (Br Med J, 2, 1976, 1225) on intestinal motility. The aim of this study was to investigate effects and mechanisms of EA on small intestinal contractions, transit, and slow waves in dogs.


METHODS
Six dogs were equipped with two intestinal cannulas for the measurement of small intestinal contractions and transit. Glucagon was used to induce postprandial intestinal hypomotility. Each dog was studied in five randomized sessions: Control, glucagon, glucagon + EA, glucagon + EA + naloxone, and glucagon + EA + atropine.


RESULTS
1 In the fasting state, EA induced intestinal contractions during motor quiescence (contractile index or CI: 4.4 ± 0.8 VS 8.3 ± 0.7, P < 0.05). 2 In the fed state, EA improved glucagon-induced intestinal hypomotility (CI: 3.8 ± 0.4 VS 6.1 ± 0.6, P < 0.05). 3 Electroacupuncture accelerated intestinal transit delayed by glucagon (67.9 ± 4.3 VS 40.2 ± 5.0 min, P < 0.05). 4 There was a negative correlation between the CI and the total transit time (R(2) = 0.59, P < 0.05). 5 The excitatory effect of EA was blocked by naloxone and partially blocked by atropine. 6 The percentage of normal slow waves was reduced with glucagon (70 ± 2%VS 98 ± 1% at baseline, P = 0.0015). Electroacupuncture normalized impaired slow waves and the effect was blocked by naloxone.


CONCLUSIONS
Electroacupuncture enhances intestinal contractions during Phase I of the migrating motor complex and glucagon-induced hypomotility in the fed state, and accelerates intestinal transit via the opioid and cholinergic pathways in dogs. Electroacupuncture may have a therapeutic potential for intestinal hypomotility.
Sun
Y
Y
Veterans Research and Education Foundation, VA Medical Center, Oklahoma City, OK, USA.
Song
G
G
Yin
J
J
Chen
J
J
Chen
J H
JH
Song
J
J
Chen
J D Z
JD
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D002490:Central Nervous System / Q000187:drug effects / Q000502:physiology; D004285:Dogs; D015671:Electroacupuncture; D004567:Electrodes, Implanted; D005215:Fasting / Q000502:physiology; D005260:Female; D005769:Gastrointestinal Motility / Q000187:drug effects*; D005772:Gastrointestinal Transit / Q000187:drug effects; D005934:Glucagon / Q000494:pharmacology*; D007421:Intestine, Small / Q000187:drug effects* / Q000294:innervation / Q000502:physiology*; D018727:Muscarinic Antagonists / Q000494:pharmacology; D009119:Muscle Contraction / Q000187:drug effects; D016065:Myoelectric Complex, Migrating / Q000187:drug effects; D009270:Naloxone / Q000037:antagonists & inhibitors / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology; D017933:Peripheral Nervous System / Q000187:drug effects / Q000502:physiology
D018727:Muscarinic Antagonists; D009292:Narcotic Antagonists; D009270:Naloxone; D001285:Atropine; D005934:Glucagon