Effect of the acupoints ST-36 (Zusanli) and SP-6 (Sanyinjiao) on intestinal myoelectric activity of Wistar rats.

Despite its ancient use as a therapeutic tool to treat several ailments, acupuncture still faces the challenge of scrutiny by Western science both in terms of its efficacy and in terms of the characterization of its effects and mechanisms of actions underlying these effects. We investigated under well-controlled and carefully characterized conditions the influence of electrical stimulation of acupuncture points ST-36 (Zusanli) and SP-6 (Sanyinjiao) on the myoelectric activity of the small intestine of 38 adult male Wistar rats. Electrical recordings obtained by means of four electrodes chronically implanted in the small intestine were used to assess the effects of acupuncture (electroacupuncture stimulation set at 2 Hz, intermittent stimulation, 1 V, for 30 min). Immobilization of the animals was associated with a consistent decrease (-8 +/- 7%) in the myoelectric activity of the small intestine as measured by means of the root mean square. Conversely, acupuncture was able to significantly increase (overshoot) this activity compared to baseline (+44 +/- 7%). In contrast, immobilized animals subjected to sham acupuncture had only modest (nonsignificant) increases in myoelectric activity (+9 +/- 6%). Using carefully controlled conditions we confirmed previous noncontrolled studies on the ability of acupuncture to alter intestinal motility. The characterization of the topographic and temporal profiles of the effects observed here represents a basis for future dissection of the physiological and pharmacological systems underlying these effects.

Effects of small bowel exclusion on intestinal myoelectrical activity pattern: comparison between innervated and denervated (transplanted) Thiry-Vella loops in rats.

Small bowel transplantation (SBT) leads to several changes in normal intestinal physiology with special reference to lymphatic disruption and graft denervation. Intestinal myoelectrical activity (MA) has been studied in different conditions, but little is known about MA in excluded bowel segments without the influence of nutrients. We performed this study to evaluate the effects of bowel exclusion on MA pattern. Fifteen Wistar rats were divided into two groups: five were used as donors and five as recipients for SBT; the remaining five underwent isolation of a jejunal segment as Thiry-Vella loop (TVL). On the 20th postoperative day, four bipolar electrodes were implanted in the small bowel of each rat: proximally and distally on the transplanted and the native intestine (SBT group); proximally and distally on the TVL and across the jejunal anastomosis (TVL group). On the 30th postoperative day, MA was recorded for 30 min after a 12 h fast. MA pattern was not altered by the exclusion of innervated jejunal segments (TVLs) with maintenance of high amplitude and migrating myoelectric complex (MMC) occurrence independent of MA in the continuity bowel. The characteristic regular spiking activity was not observed in transplanted grafts and MA analysis showed slow waves containing superimposed irregular spiking activity.

Effect of the acupoints ST-36 (Zusanli) and SP-6 (Sanyinjiao) on intestinal myoelectric activity of Wistar rats

Despite its ancient use as a therapeutic tool to treat several ailments, acupuncture still faces the challenge of scrutiny by Western science both in terms of its efficacy and in terms of the characterization of its effects and mechanisms of actions underlying these effects. We investigated under well-controlled and carefully characterized conditions the influence of electrical stimulation of acupuncture points ST-36 (Zusanli) and SP-6 (Sanyinjiao) on the myoelectric activity of the small intestine of 38 adult male Wistar rats. Electrical recordings obtained by means of four electrodes chronically implanted in the small intestine were used to assess the effects of acupuncture (electroacupuncture stimulation set at 2 Hz, intermittent stimulation, 1 V, for 30 min). Immobilization of the animals was associated with a consistent decrease (-8 ± 7 percent) in the myoelectric activity of the small intestine as measured by means of the root mean square. Conversely, acupuncture was able to significantly increase (overshoot) this activity compared to baseline (+44 ± 7 percent). In contrast, immobilized animals subjected to sham acupuncture had only modest (nonsignificant) increases in myoelectric activity (+9 ± 6 percent). Using carefully controlled conditions we confirmed previous noncontrolled studies on the ability of acupuncture to alter intestinal motility. The characterization of the topographic and temporal profiles of the effects observed here represents a basis for future dissection of the physiological and pharmacological systems underlying these effects