Effects of acupuncture on vasopressin-induced emesis in conscious dogs

Abstract

Although acupuncture has a significant clinical benefit, the mechanism of acupuncture remains unclear. Vasopressin, a posterior pituitary hormone, is involved in nausea and vomiting in humans and dogs. To investigate the antiemetic effects of acupuncture on vasopressin-induced emesis, gastroduodenal motor activity and the frequency of retching and vomiting were simultaneously recorded in conscious dogs. In seven dogs, four force transducers were implanted on the serosal surfaces of the gastric body, antrum, pylorus, and duodenum. Gastroduodenal motility was continuously monitored throughout the experiment. Vasopressin was intravenously infused at a dose of 0.1 U x kg(-1) x min(-1) for 20 min. Electroacupuncture (EA, 1-30 Hz) at pericardium-6 (PC6), bladder-21 (BL21), or stomach-36 (ST36) was performed before, during, and after the vasopressin infusion. To investigate whether the opioid pathway is involved in EA-induced antiemetic effects, naloxone (a central and peripheral opioid receptor antagonist) or naloxone methiodide (a peripheral opioid receptor antagonist) was administered before, during, and after EA and vasopressin infusion. Intravenous infusion of vasopressin induced retching and vomiting in all dogs tested. Retrograde peristaltic contractions occurred before the onset of retching and vomiting. EA (10 Hz) at PC6 significantly reduced the number of episodes of retching and vomiting. EA at PC6 also suppressed retrograde peristaltic contractions. In contrast, EA at BL21 or ST36 had no antiemetic effects. The antiemetic effect of EA was abolished by pretreatment with naloxone but not naloxone methiodide. It is suggested that the antiemetic effect of acupuncture is mediated via the central opioid pathway.

Electroacupuncture improves impaired gastric motility and slow waves induced by rectal distension in dogs

“…EA at acupoints located on the back [bladder-21 (BL21)] were used for sham acupuncture. BL21 is located 1 cm lateral of the spinous process of the 12th thoracic vertebrae (45).…”

“…It may be mediated via the neural reflex, and either the nociceptive or nonnociceptive afferent pathway is involved, which is correlated with distension volumes and visceral sensation (19). More recent studies showed that sympathovagal balance was altered in IBS patients (23,41,45), but it is not clear whether these activities are altered with RD.Acupuncture is a traditional Chinese medicine involving stimulation of the acupoints in the skin by thin, metallic needles that are manipulated manually or combined with electrical stimulation, a procedure referred to as electroacupuncture (EA). Acupressure is a noninvasive medical technique conducted by pressing on the acupoints with the fingers or by an embedded stud over the acupoints.…”

“…It may be mediated via the neural reflex, and either the nociceptive or nonnociceptive afferent pathway is involved, which is correlated with distension volumes and visceral sensation (19). More recent studies showed that sympathovagal balance was altered in IBS patients (23,41,45), but it is not clear whether these activities are altered with RD.…”

Holistic Acupuncture approach to idiopathic refractory nausea, abdominal pain and bloating

“…Based on the effect of acupuncture on the heart rate variability, it was concluded that this effect was associated with increased vagal activity. A central effect of electroacupuncture has also been suggested by Tatewaki et al [19] who demonstrated that electroacupuncture at PC6 reduced the number of retching and vomiting episodes following vasopressin injection in dogs, an anti-emetic effect which was abolished by pretreatment with naloxone. Whether this proves to be similar for humans is unknown.…”

Role of physiologic issues in future therapy of rheumatoid arthritis I. Chronic inflammation toward action of parasympathetic system

“…[28,29] pobudzający wpływ akupunktury był hamowany właśnie przez atropinę i heksametonium, czyli znane parasympatykolityki. Okazało się jednak, że aktywujący wpływ akupunktury nie był obserwowany u szczurów po dokonanej wagotonii.…”