title: Involvement of adenosine A1 and A2A receptors in (-)-linalool-induced antinociception.
abstract: In recent studies performed in our laboratory we have shown that acute administration of (-)-linalool, the natural occurring enantiomer in essential oils, possesses anti-inflammatory, antihyperalgesic and antinociceptive effects in different animal models. The antihyperalgesic and antinociceptive effects of (-)-linalool have been ascribed to its capacity in stimulating the opioidergic, cholinergic and dopaminergic systems, as well as to its interaction with K+ channels, or to its local anaesthetic activity and/or to the negative modulation of glutamate transmission. Activation of A1 or A2A receptors has been shown to induce antinociceptive effects, and the possible involvement of adenosine in (-)-linalool antinociceptive effect, has not been elucidated yet. Therefore, in the present study, we have investigated the effects of 1,3-dipropyl-8-cyclopentylxanthine (DPCPX), a selective adenosine A1 receptor antagonist and the effects of 3,7-dimethyl-1-propargilxanthine (DMPX), a selective adenosine A2A receptor antagonist on the antinociception of (-)-linalool in mice, measured in the hot-plate test. Both DPCPX (0.1 mg/kg; i.p.) and DMPX (0.1 mg/kg; i.p.) pre-treatment significantly depressed the antinociceptive effect of (-)-linalool at the highest doses tested. These findings demonstrated that the effect of (-)-linalool on pain responses is, at least partially, mediated by the activity of adenosine A1 and A2A receptors.
authors.affiliation: Dipartimento di Scienze del Farmaco, Università degli Studi di Sassari, via Muroni 23/a, 07100 Sassari, Italy. apeana@uniss.it
authors.forename: Alessandra T
authors.initials: AT
authors.lastname: Peana
authors.forename: Paolo
authors.initials: P
authors.lastname: Rubattu
authors.forename: Gian Giorgio
authors.initials: GG
authors.lastname: Piga
authors.forename: Silvia
authors.initials: S
authors.lastname: Fumagalli
authors.forename: Giampiero
authors.initials: G
authors.lastname: Boatto
authors.forename: Proto
authors.initials: P
authors.lastname: Pippia
authors.forename: M Graziella
authors.initials: MG
authors.lastname: De Montis
mesh_terms: D000080462:Acyclic Monoterpenes; D058916:Adenosine A1 Receptor Antagonists; D058917:Adenosine A2 Receptor Antagonists; D000700:Analgesics; D000818:Animals; D006358:Hot Temperature; D008297:Male; D051379:Mice; D039821:Monoterpenes / Q000494:pharmacology*; D010147:Pain Measurement / Q000187:drug effects; D011930:Reaction Time / Q000187:drug effects; D043682:Receptor, Adenosine A1 / Q000187:drug effects / Q000502:physiology*; D043705:Receptor, Adenosine A2A / Q000187:drug effects / Q000502:physiology*; D013805:Theobromine / Q000031:analogs & derivatives / Q000494:pharmacology; D014970:Xanthines / Q000494:pharmacology
chemical_list: D000080462:Acyclic Monoterpenes; D058916:Adenosine A1 Receptor Antagonists; D058917:Adenosine A2 Receptor Antagonists; D000700:Analgesics; D039821:Monoterpenes; D043682:Receptor, Adenosine A1; D043705:Receptor, Adenosine A2A; D014970:Xanthines; C057837:3,7-dimethyl-1-propargylxanthine; C051360:1,3-dipropyl-8-cyclopentylxanthine; C018584:linalool; D013805:Theobromine