Search

Background and Purpose: Hyper-nociceptive PGE2 EP4 receptors and prostacyclin (IP) receptors are present in adult rat dorsal root ganglion (DRG) neurones and glial cells in culture. The present study has investigated the cell-specific expression of two other Gs-protein coupled hyper-nociceptive receptor systems: β-adrenoceptors and calcitonin gene-related peptide (CGRP) receptors in isolated DRG cells and has examined the influence of neurone-glial cell interactions in regulating adenylyl cyclase (AC) activity. Experimental Approach: Agonist-stimulated AC activity was determined in mixed DRG cell cultures from adult rats and compared with activity in DRG neurone-enriched cell cultures and pure DRG glial cell cultures. Key Results: Pharmacological analysis showed the presence of Gs-coupled β2-adrenoceptors and CGRP receptors, but not β1-adrenoceptors, in all three DRG cell preparations. Agonist-stimulated AC activity was weakest in DRG neurone-enriched cell cultures. DRG neurones inhibited IP receptor-stimulated glial cell AC activity by a process dependent on both cell-cell contact and neurone-derived soluble factors, but this is unlikely to involve purine or glutamine receptor activation. Conclusions and Implications Gs-coupled hyper-nociceptive receptors are readily expressed on DRG glial cells in isolated cell cultures and the activity of CGRP, EP4 and IP receptors, but not β2-adrenoceptors, in glial cells is inhibited by DRG neurones. Studies using isolated DRG cells should be aware that hyper-nociceptive ligands may stimulate receptors on glial cells in addition to neurones, and that variable numbers of neurones and glial cells will influence absolute measures of AC activity and affect downstream functional responses. British Journal of Pharmacology © 2012 The British Pharmacological Society.

Yeung, Barry Ho Sing., Thesis (M.Phil.)--Chinese University of Hong Kong, 2011., Includes bibliographical references (leaves 137-154)., s in English and Chinese., p.i, 論文摘要 --- p.iv, Acknowledgements --- p.vii, Publications based on work in this thesis. --- p.ix, List of abbreviations --- p.x, Chapter Chapter 1 --- Introduction --- p.1, Chapter 1.1 --- Dorsal root ganglion cells --- p.1, Chapter 1.1.1 --- Primary sensory neurons --- p.1, Chapter 1.1.2 --- Non-neuronal cells --- p.3, Chapter 1.1.2.1 --- Satellite glial cells --- p.3, Chapter 1.1.2.2 --- Schwann cells --- p.6, Chapter 1.2 --- Peripheral sensitization --- p.8, Chapter 1.3 --- Neuron-glia interactions --- p.9, Chapter 1.4 --- Aim of Thesis --- p.11, Chapter Chapter 2 --- "Materials, media, buffers and solutions" --- p.13, Chapter 2.1 --- Materials --- p.13, Chapter 2.2 --- "Culture media, buffer and solutions" --- p.19, Chapter 2.2.1 --- Culture media --- p.19, Chapter 2.2.2 --- General culture buffers and culture plate coating reagents --- p.19, Chapter 2.3 --- Antibodies used for identifying DRG cells --- p.23, Chapter 2.3.1 --- Primary antibodies --- p.23, Chapter 2.3.2 --- Secondary antibodies --- p.23, Chapter Chapter 3 --- Methods --- p.24, Chapter 3.1 --- Preparation of DRG cell cultures --- p.24, Chapter 3.2 --- Preparation of neuron-enriched and glial cell cultures --- p.25, Chapter 3.3 --- Immunocytochemistry --- p.26, Chapter 3.4 --- Immunohistochemistry --- p.27, Chapter 3.4 --- Determination of [3H]cAMP production in DRG cells --- p.28, Chapter 3.4.1 --- Principle of assay --- p.28, Chapter 3.4.2 --- Loading DRG cells with [3H]adenine --- p.28, Chapter 3.4.3 --- Column preparation --- p.28, Chapter 3.4.4 --- Measurement of [3H]cAMP production in DRG cells --- p.29, Chapter 3.4.5 --- Data analysis --- p.30, Chapter Chapter 4 --- Identification of DRG cells in dissociated cultures --- p.31, Chapter 4.1 --- Introduction --- p.31, Chapter 4.2 --- Aim of study --- p.34, Chapter 4.3 --- Results --- p.35, Chapter 4.3.1 --- Identification of DRG cells in isolated cultures --- p.35, Chapter 4.3.2 --- Activation and proliferation of glial cells in isolated cell cultures --- p.36, Chapter 4.3.3 --- Identification of glial cells in cultures --- p.38, Chapter 4.3.4 --- Modification of staining methods --- p.40, Chapter 4.3.5 --- Immunohistochemistry to identify DRG cells in DRG slices --- p.42, Chapter 4.3.6 --- Comparison of antibody staining in whole DRG and isolated DRG cells --- p.44, Chapter 4.4 --- Discussion --- p.44, Chapter 4.5 --- Summary --- p.53, Chapter Chapter 5 --- Characterization of GPCRs in isolated DRG cultures --- p.69, Chapter 5.1 --- Introduction --- p.69, Chapter 5.1.1 --- G-protein coupled receptors --- p.69, Chapter 5.1.2 --- Pharmacological characterization of prostanoid receptors on DRG cells --- p.73, Chapter 5.1.3 --- Gs- and Gi/o-coupled GPCRs in DRG cells --- p.75, Chapter 5.1.3.1 --- Gs-coupled GPCR: β-adrenoceptors --- p.76, Chapter 5.1.3.2 --- Gs-coupled GPCR: CGRP receptors --- p.79, Chapter 5.1.3.3 --- Gi/o-coupled GPCR: α2-adrenoceptors --- p.82, Chapter 5.1.3.4 --- Gi/o-coupled GPCR: Cannabinoid receptors --- p.85, Chapter 5.1.3.5 --- Gi/o-coupled GPCR: 5-HT1Areceptors --- p.88, Chapter 5.1.3.6 --- Gi/o-coupled GPCR: opioid and opioid-receptor-like 1 receptors --- p.90, Chapter 5.2 --- Aims of study --- p.93, Chapter 5.3 --- Results --- p.94, Chapter 5.3.1 --- Characterization of prostanoid receptors in isolated DRG cells --- p.94, Chapter 5.3.2 --- Characterization of CGRP receptors in isolated DRG cells --- p.96, Chapter 5.3.3 --- Investigation of the effect of CGRP8.37 on CGRP responses --- p.97, Chapter 5.3.4 --- Characterization of β1-adrenoceptors in isolated DRG cells --- p.97, Chapter 5.3.5 --- Characterization of β2-adrenoceptors in isolated DRG cells --- p.98, Chapter 5.3.6 --- Identification of β-adrenoceptor subtype mediating isoprenaline-stimulated responses.. --- p.99, Chapter 5.3.7 --- Characterization of α2-adrenceptors in isolated DRG cells --- p.100, Chapter 5.3.8 --- Characterization of cannabinoid 1 receptors in isolated DRG cells ... --- p.100, Chapter 5.3.9 --- Characterization of cannabinoid 2 receptors in isolated DRG cells --- p.101, Chapter 5.3.10 --- Characterization of 5-HT1A receptors in isolated DRG cells --- p.101, Chapter 5.3.11 --- Characterization of μ-opioid receptors in isolated DRG cells --- p.102, Chapter 5.3.12 --- Characterization of opioid-receptor-like 1 receptors in isolated DRG cells --- p.102, Chapter 5.3.13 --- Effect of nerve growth factor on DRG cells --- p.103, Chapter 5.4 --- Discussion --- p.106, Chapter 5.5 --- Summary --- p.114, Chapter Chapter 6 --- Conclusion and further studies --- p.134, References --- p.137, http://library.cuhk.edu.hk/record=b5894627, Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/)