Feishu Acupuncture Inhibits Acetylcholine Synthesis and Restores Muscarinic Acetylcholine Receptor M2 Expression in the Lung When Treating Allergic Asthma

Abstract

Acupuncture was proven beneficial in treating allergic inflammation. We aimed to explore the regulation underlying the effects of acupuncture on Feishu, an acupoint most commonly used in the acupuncture therapy for respiratory diseases, with respect to the system of sympathetic nerve neurotransmitter acetylcholine (Ach). Male Wistar rats were randomly grouping. No treatment was taken in the normal group. Allergic asthma was induced using ovalbumin on the model, Feishu acupuncture, and sham acupuncture groups; then control or acupuncture treatment lasting for 3 weeks was performed. Bronchoalveolar lavage fluid (BALF) from the four groups was examined. And pulmonary tissues were subjected to histological analysis with H&E staining; besides, immunofluorescent staining, quantitative PCR, and western blot were used to detect synthetase (ChAT) and Ach hydrolase (AchE), and its muscarinic receptors (mAchRs) M1-M3. There was inflammatory infiltration in the lung upon allergic asthma, which was alleviated by the Feishu acupuncture. The eosinophilic granulocytes, neutrophils, and lymphocytes in BALF from the Feishu acupuncture group were all significantly decreased compared with those of the model and sham acupuncture groups. The specific acupuncture on Feishu upon allergic asthma put down the pulmonary expression of ChAT, repaired at the level of gene expression the pulmonary expression of mAchR M1, and restored the pulmonary expression of mAchR M2 (especially in the bronchiolar epithelium) which has a role in inhibiting Ach release; while sham acupuncture had no effect. These results confirmed the therapeutic effects of Feishu acupuncture on allergic asthma, suggesting that the mechanisms may involve suppression of the Ach signal both from its synthesis and during its release.

Keywords: Feishu acupoint; acetylcholine; acupuncture; allergic asthma; choline acetyltransferase; muscarinic acetylcholine receptor.