title: Involvement of mGluR5 in the ethanol-induced neuropathic pain-like state in the rat.
abstract: Alcohol neuropathy has been thought to involve decreased nerve function following chronic ethanol consumption. However, there is no reliably successful therapy, largely due to a lack of understanding of the central underlying mechanisms. The aim of this study was to investigate the mechanisms that contribute to the neuropathic pain-like state induced by chronic ethanol treatment in rats. Rats were chronically treated with ethanol diet (1.25-5% of ethanol) for over 70 days. Mechanical hyperalgesia was observed during ethanol consumption and even after ethanol withdrawal. Under these conditions, an immunohistochemical study showed an increase in metabotropic glutamate receptor 5 (mGluR5) immunoreactivity in the superficial spinal dorsal horn of chronic ethanol-fed rats. Furthermore, immunoblot analysis revealed that the protein level of mGluR5 was clearly increased following chronic ethanol consumption. These findings support the idea that the increased levels of mGluR5 in the spinal cord may be, at least in part, involved in the induction of ethanol-dependent neuropathic pain-like state.
authors.affiliation: Department of Toxicology, Hoshi University School of Pharmacy and Pharmaceutical Sciences, 2-4-41 Ebara, Tokyo 142-8501, Japan.
authors.forename: Kan
authors.initials: K
authors.lastname: Miyoshi
authors.forename: Minoru
authors.initials: M
authors.lastname: Narita
authors.forename: Michiko
authors.initials: M
authors.lastname: Narita
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Suzuki
mesh_terms: D020269:Alcoholic Neuropathy / Q000139:chemically induced / Q000150:complications / Q000378:metabolism*; D000818:Animals; D015153:Blotting, Western / Q000379:methods; D000431:Ethanol; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D010146:Pain / Q000209:etiology / Q000378:metabolism*; D051381:Rats; D011916:Rats, Inbred F344; D064529:Receptor, Metabotropic Glutamate 5; D018094:Receptors, Metabotropic Glutamate / Q000378:metabolism*; D013997:Time Factors
chemical_list: C578937:Grm5 protein, rat; D064529:Receptor, Metabotropic Glutamate 5; D018094:Receptors, Metabotropic Glutamate; D000431:Ethanol