Ameliorating effects of auricular electroacupuncture on rectal distention-induced gastric dysrhythmias in rats.

Gastric slow waves (GSW) are known to regulate gastric motility and are impaired with rectal distention (RD). Electroacupuncture (EA) at body acupoints, such as ST 36, has been shown to improve gastric dysrhythmias; however, little is known about the possible effects of auricular electroacupuncture (AEA) on GSW. To study effects and possible mechanisms of AEA on RD-induced gastric dysrhythmias in rats, ten male Sprague-Dawley (SD) rats implanted with gastric serosal electrodes were studied in two different experiments in fed state. Four sessions were performed in experiment 1 as follows: control (RD, no stimulation), RD+AEA, RD+EA at body points and RD+sham AEA. Two sessions were included in experiment 2 to study mechanisms of AEA: RD + atropine and RD + atropine + AEA. It was found that 1) RD significantly decreased the percentage of normal GSW from 89.8 ± 3.5% to 76.0 ± 3.3% (P<0.05); 2) AEA increased the percentage of normal GSW during RD to 94.0 ± 2.1% (P<0.05 vs. RD) via a reduction in the percentages of tachygastria and arrhythmia (P