Inhibition of acid secretion by electrical acupuncture is mediated via beta-endorphin and somatostatin

Abstract

Electroacupuncture (EAP) was shown to inhibit basal gastric acid secretion in dogs and sham feeding-stimulated acid secretion in humans. However, its effect on a meal-stimulated acid secretion in dogs and the mechanisms involved remain unclear. In five dogs prepared with gastric cannulas, gastric acid secretion was determined by a dye-dilution technique for 60 min after intragastric administration of 200 ml of 4% mixed amino acid meal in six different experiments: study 1, no acupuncture; study 2, sham acupuncture (SAP); study 3, EAP; study 4, EAP plus naloxone; study 5, naloxone alone; and study 6, intravenous infusion of somatostatin (SS) and vasoactive intestinal peptide (VIP) at doses of 0.5 and 1.0 micrograms.kg-1.h-1, respectively. EAP was performed on three different points including Pishu, ZusanLi, and Neiguan. Biphasic electrical pulse (25-100 Hz, 12-16 mA) was applied continuously via needles for 75 min starting 15 min before meal. SAP on nonacupoints in hind- and forelegs was performed with the same electrical pulse. Plasma SS, VIP, beta-endorphin, and gastrin were determined by specific radioimmunoassays. EAP significantly inhibited acid secretion (75%; P < 0.01), which coincided with significant increases in plasma SS, VIP, and beta-endorphin and a significant decrease in plasma gastrin. Naloxone completely reversed EAP-induced inhibition of acid secretion and changes in plasma concentration of peptides. SAP also significantly suppressed acid output (30%; P < 0.05), with a modest but significant increase in plasma beta-endorphin. However, the inhibition by EAP on the acid output was significantly greater than that by SAP (P < 0.01). Furthermore, exogenous SS (0.5 microgram.kg-1.h-1) significantly inhibited acid output (78%), whereas VIP failed to inhibit gastric acid secretion. We conclude that, in dogs, EAP significantly inhibits meal-stimulated acid secretion. This acid inhibition is mediated by the release of beta-endorphin and somatostatin, and an endogenous opiate or opiates appear to play an important role in the release of SS, VIP, and beta-endorphin.

Changes in Serum Leptin and Beta Endorphin Levels with Weight Loss by Electroacupuncture and Diet Restriction in Obesity Treatment

“…Increase in BE both in the central nervous system and plasma with EA application has been observed in humans (Jin et al, 1996) and animals (Takeshige et al, 1993;Pan et al, 1996;Petti et al, 1998). It has been particularly observed that there is a strong relationship between an acupuncture-induced analgesic effect and the existence of BE in brain tissue (Ullet et al, 1998) and that the analgesic effect of EA application is more effective than that of acupuncture application (Wang et al, 1992).…”

Acupuncture in Critically Ill Patients Improves Delayed Gastric Emptying

“…25 Furthermore, several experimental studies on animals have demonstrated a possible modulating effect of acupoint stimulation on variables of gastric motility and acid secretion. 26-30 Finally, acupuncture and other forms of acupoint stimulation on acupoint Neiguan were found superior to placebo procedures for PONV and also highly effective against chemotherapy-induced or pregnancy-related nausea and vomiting. 31-33 …”

Acupuncture Reduces Crying in Infants with Infantile Colic: A Randomised, Controlled, Blind Clinical Study

“…Stimulating LI4 bilaterally resulted in more immediate effect than unilateral stimulation 39. The motility in the intestinal tract and the gastric acid secretion increased or decreased depending on which points were needled 29 30 32 45 46. In human adults47–49 and children50 acupuncture had a beneficial effect on visceral symptoms like nausea.…”