The First Hospital of Peking University, China-Research, has shown that electroacupuncture at Pericardium Meridian Point 6 (PC6 or Nei Guan - Pericardium Meridian) may decrease the frequency of transient lower esophageal sphincter relaxation (TLESR), which is the main mechanism underlying gastroesophageal reflux disease (GERD).
The study is reported in Issue 35 (September, 2007) of the World Journal of Gastroenterology because of its significant clinical impact.
The study found that electroacupuncture at PC6 can contribute to a decrease of TLESR induced by gastric distention in cats. It also showed that this effect appears to act at the brain stem, and may be mediated through nitric oxide (NO), CCK-A, and mu-opioid receptors.
"Acupuncture has been used to treat functional gastrointestinal disorders in Eastern countries for centuries. Our research aimed to investigate the relationship between acupuncture and TLESR and to discuss its mechanisms," noted principal investigator Peng-Yan Xie, professor and chair of the Department of Gastroenterology at the First Hospital of Peking University. "This research is the first paper to carefully observe the mechanisms of this phenomenon."
The study involved two experiments. One showed that electroacupuncture at PC6 decreased the frequency of TLESR induced by gastric distention in cats, and that it may act at the reticular formation of medulla (RFM) in the brain stem.
In the second experiment, Xie and his colleagues pretreated the cats with saline (2 mL iv. control group), phaclofen (5 mg/kg iv. GABA-B antagonist), cholecystokinin octapeptide (CCK-8) (1 mug/kg/h iv.), L-Arginine (200 mg/kg iv.), naloxone (2.5 mumol/kg iv.) and tacrine (5.6 mg/kg ip. cholinesterase inhibitor) respectively before electroacupuncture at PC6, and observed whether the effect of the electroacupuncture was reversed. They found that CCK-8, L-arginine and naloxone reversed the effect of acupuncture. On the other hand, phaclofen and tacrine did not have such an effect.
The main conclusion reported by the investigators is that electric acupoint stimulation at the PC6 results in a significant reduction of the rate of TLESRs induced by gastric distention. This effect appears to act at the brain stem, and may be mediated through NO, CCK-A, and mu-opioid receptors.