Ameliorating effects of electroacupuncture on dysmotility, inflammation and pain mediated via the autonomic mechanism in a rat model of postoperative ileus
<p>Objective:
Postoperative ileus increases healthcare costs and reduces the postoperative qualify
of life. The aim of this study was to investigate effects and mechanisms of
electroacupuncture (EA) at ST36 and PC6 on gastrointestinal motility in a rat model
of postoperative ileus.</p>
<p>Methods:
Laparotomy was performed in 24 rats (control, sham-EA and EA) for the implantation
of serosal electrodes in the stomach and mid-jejunum for measuring gastric and small
intestinal slow waves, respectively; electrodes were also placed in the chest
underneath the skin for measuring the ECG. Intestinal manipulation (IM, to
induce ileus) was performed in 16 rats and immediately after the surgical
procedures, EA was performed in 8 rats and sham-EA in the other 8 rats. Small
intestinal transit, gastric emptying, postoperative pain, and plasma TNF-α were
evaluated in the three groups of rats. </p>
<p>Results:
1) Compared with sham-EA, EA accelerated both small intestinal transit (P < 0.05)
and gastric emptying (P < 0.05) and improved regularity of small intestinal
slow waves. 2) Compared with the control rats (no-IM), IM suppressed vagal
activity and increased sympathovagal ratio assessed by the spectral analysis of
heart rate variability derived from the ECG, which were significantly prevented
by EA. 3) EA significantly reduced pain score at 120min (P<0.05, vs 15 min)
after the surgery, which was not seen with sham-EA. 4) Plasma TNF- α was increased
by IM (P = 0.02) but suppressed by EA (P = 0.04) but not sham-EA.</p>
<p>Conclusions:
In a rodent model of postoperative ileus induced by IM, EA at ST36 and PC6
exerts a prokinetic effect on gastric emptying and small intestinal transit, a regulatory
effect on small intestinal slow waves and an analgesic effect on postoperative
pain possibly mediated via the autonomic-cytokine mechanisms.</p
