Please use this identifier to cite or link to this item: http://hdl.handle.net/2440/122657
Citations
Scopus Web of Science® Altmetric
?
?
Type: Journal article
Title: Biphasic effects of methanandamide on murine gastric vagal afferent mechanosensitivity
Author: Christie, S.
O'Reilly, R.
Li, H.
Wittert, G.A.
Page, A.J.
Citation: The Journal of Physiology, 2020; 598(1):139-150
Publisher: Wiley
Issue Date: 2020
ISSN: 0022-3751
1469-7793
Statement of
Responsibility: 
Stewart Christie, Rebecca O’Rielly, Hui Li, Gary A. Wittert and Amanda J. Page
Abstract: Gastric vagal afferents (GVAs) signal to the hindbrain resulting in satiety. Endocannabinoids are endogenous ligands of cannabinoid 1 receptor (CB1) and transient receptor potential vanilloid‐1 (TRPV1) channels. The endocannabinoid anandamide (AEA) is expressed in the stomach, and its receptor CB1 is expressed in ghrelin‐positive gastric mucosal cells. Further, TRPV1, CB1 and growth hormone secretagogue receptor (ghrelin receptor, GHSR) are expressed in subpopulations of GVA neurons. This study aimed to determine the interaction between TRPV1, CB1, GHSR and endocannabinoids in the modulation of GVA signalling. An in vitro electrophysiology preparation was used to assess GVA mechanosensitivity in male C57BL/6 mice. Effects of methanandamide (mAEA; 1–100 nm), on GVA responses to stretch were determined in the absence and presence of antagonists of CB1, TRPV1, GHSR, protein kinase‐A (PKA), protein kinase‐C (PKC) and G‐protein subunits Gαi/o, or Gαq. Low doses (1–10 nm) of mAEA reduced GVA responses to 3 g stretch, whereas high doses (30–100 nm) increased the response. The inhibitory and excitatory effects of mAEA (1–100 nm) were reduced/lost in the presence of a CB1 and TRPV1 antagonist. PKA, Gαi/o or GHSR antagonists prevented the inhibitory effect of mAEA on GVA mechanosensitivity. Conversely, in the presence of a PKC or Gαq antagonist the excitatory effect of mAEA was reduced or lost, respectively. Activation of CB1, by mAEA, can activate or inhibit TRPV1 to increase or decrease GVA responses to stretch, depending on the pathway activated. These interactions could play an important role in the fine control of food intake.
Keywords: Anandamide; gastric vagal afferent; TRPV1
Rights: © 2019 The Authors. The Journal of Physiology © 2019 The Physiological Society
RMID: 1000003767
DOI: 10.1113/jp278696
Grant ID: http://purl.org/au-research/grants/nhmrc/1159744
Appears in Collections:Medicine publications

Files in This Item:
There are no files associated with this item.


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.