title: Spinal cholinergic involvement after treatment with aspirin and paracetamol in rats.
abstract: Aspirin and paracetamol have been shown to suppress non-inflammatory pain conditions like thermal, visceral and mechanical pain in mice and rats. The non-inflammatory antinociception appears to be mediated by central receptor mechanisms, such as the cholinergic system. In this study, we tested the hypothesis that the non-inflammatory antinociception of aspirin and paracetamol could be mediated by an increase of intraspinal acetylcholine release. Microdialysis probes were placed intraspinally in anesthetized rats for acetylcholine sampling. Subcutaneously administered aspirin 100 and 300 mg/kg increased, while paracetamol 300 mg/kg decreased intraspinal acetylcholine release. Intraspinal drug administration did not affect acetylcholine release. Our results suggest that an increased intraspinal acetylcholine release could be involved in part of the non-inflammatory pain suppression by aspirin, but not by paracetamol.
authors.affiliation: Department of Neuroscience, Division of Comparative Medicine, Biomedical Center, Uppsala University, P.O. Box 572, S-751 23 Uppsala, Sweden. klas.abelson@fysiologi.uu.se
authors.forename: Klas S P
authors.initials: KS
authors.lastname: Abelson
authors.forename: Mahinda
authors.initials: M
authors.lastname: Kommalage
authors.forename: A Urban
authors.initials: AU
authors.lastname: Höglund
mesh_terms: D000082:Acetaminophen / Q000494:pharmacology*; D000109:Acetylcholine / Q000494:pharmacology; D018712:Analgesics, Non-Narcotic / Q000494:pharmacology*; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000494:pharmacology*; D001241:Aspirin / Q000008:administration & dosage / Q000494:pharmacology*; D001831:Body Temperature / Q000187:drug effects; D007279:Injections, Subcutaneous; D008297:Male; D017551:Microdialysis; D010146:Pain / Q000503:physiopathology; D010275:Parasympathetic Nervous System / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000502:physiology*
chemical_list: D018712:Analgesics, Non-Narcotic; D000894:Anti-Inflammatory Agents, Non-Steroidal; D000082:Acetaminophen; D000109:Acetylcholine; D001241:Aspirin