title: β1/2 or M2/3 Receptors Are Required for Different Gastrointestinal Motility Responses Induced by Acupuncture at Heterotopic or Homotopic Acupoints.
abstract: Acupuncture at homotopic acupoints or heterotopic acupoints is known to either inhibit or facilitate gastrointestinal motility, depending on the acupoint location. However, little effort has been made to investigate the roles of specific receptors (such as adrenergic and muscarinic acetylcholine receptors) in mediating the effects of acupuncture at heterotopic and homotopic acupoints. Different adrenergic receptor subtypes or cholinergic receptor subtypes are predominantly expressed in various sections of the gut, resulting in variations between the effects of acupuncture at heterotopic or homotopic acupoints on gastrointestinal motility. Here, we investigated the role of β1/β2 receptors and M2/M3 receptors in gastrointestinal motility regulated by acupuncture at ST37, a heterotopic acupoint, and ST25, a homotopic acupoint, by simultaneously recording intraluminal pressures in the distal colon and stomach or jejunum and examining fecal phenol red excretion in β1/2 receptor-knockout mice and M2/3 receptor-knockout mice. We found that knockout of the M2/3 receptor significantly inhibited ST37 acupuncture-induced enhancement of gastric motility, jejunal motility, and colonic motility. Additionally, knocking out of the β1/2 receptor significantly diminished the ST25 acupuncture-induced inhibition of gastric motility and jejunal motility without significantly altering the enhancement of colonic motility induced by acupuncture at ST25. Acupuncture at ST37 significantly accelerated gastrointestinal transition in β1/2 receptor-knockout mice and their wild-type littermates. However, this acceleration of gastrointestinal transition was markedly diminished in M2/3 receptor-knockout mice relative to their wild-type littermates. Acupuncture at ST25 significantly increased gastrointestinal transition in β1/2 receptor-knockout mice and significantly decreased gastrointestinal transition in M2/3 receptor-knockout mice without altering gastrointestinal transition in wild-type littermates of either. Our study revealed that M2/3 receptors are required for the gastrointestinal motility associated with whole gastrointestinal transition enhanced by acupuncture at heterotopic acupoints, whereas β1/2 receptors are required for the same gastrointestinal motility processes inhibited by acupuncture at homotopic acupoints. Therefore, our findings reveal important biological mechanisms underlying acupuncture treatment of disorders involving gastrointestinal motility dysfunction.
authors.affiliation: Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China.
authors.forename: Xinyan
authors.initials: X
authors.lastname: Gao
authors.affiliation: Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China.
authors.forename: Yuxue
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China.
authors.forename: Yangshuai
authors.initials: Y
authors.lastname: Su
authors.affiliation: Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Liu
authors.affiliation: Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China.
authors.forename: Xiaochun
authors.initials: X
authors.lastname: Yu
authors.affiliation: Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China.|People's Hospital of Ri Zhao, Rizhao, China.
authors.forename: Changxiang
authors.initials: C
authors.lastname: Cui
authors.affiliation: Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China.
authors.forename: Zhaokun
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Shi
authors.affiliation: Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China.
authors.forename: Xianghong
authors.initials: X
authors.lastname: Jing
authors.affiliation: Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Zhu
mesh_terms: D015669:Acupuncture Points; D015670:Acupuncture Therapy; D000818:Animals; D005769:Gastrointestinal Motility / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D043585:Receptor, Muscarinic M2 / Q000235:genetics / Q000378:metabolism*; D043587:Receptor, Muscarinic M3 / Q000235:genetics / Q000378:metabolism*; D018342:Receptors, Adrenergic, beta-1 / Q000235:genetics / Q000378:metabolism*; D018343:Receptors, Adrenergic, beta-2
chemical_list: D043585:Receptor, Muscarinic M2; D043587:Receptor, Muscarinic M3; D018342:Receptors, Adrenergic, beta-1; D018343:Receptors, Adrenergic, beta-2