The contribution of lysophosphatidic acid receptors in the response of human lower esophageal sphincter under the electrical field stimulation

BACKGROUND: This study aims to identify the impact on the reaction while the clasp and sling fibers of the human lower esophageal sphincter are under the electrical field stimulation, by adding lysophosphatidic acid receptor subtypes antagonist. METHODS: Between March 2018 to December 2018, muscle strips were isolated from 28 patients who underwent esophagectomy for mid-third esophageal carcinomas. Muscle tension measurement technique in vitro and electrical field stimulation were used to examine the effects of selective lysophosphatidic acid receptor antagonist on the clasp and sling fibers of human lower esophageal sphincter. RESULTS: The optimal frequency of frequency-dependent relaxation in clasp fibers and contraction in sling fibers induced by electrical field stimulation is 64 Hz and 128 Hz respectively. The selective lysophosphatidic acid 1 and 3 receptor antagonist produced no significant difference in the frequency-dependent relaxation in clasp fibers and contraction in sling fibers induced by the electrical field stimulation (P > 0.05). CONCLUSION: The electrical field stimulation induced a frequency-dependent relaxation in clasp fibers and contraction in sling fibers. The lysophosphatidic acid 1 and 3 receptors are not involved in the response of clasp and sling fibers of the human lower esophageal sphincter induced by the electrical field stimulation.