www.elsevier.com/locate/brainres Available online at www.sciencedirect.com Research Report Effects of Se-phenyl thiazolidine-4-carboselenoate on mechanical and thermal hyperalgesia in brachial plexus avulsion in mice: Mediation by cannabinoid CB 1 and CB 2 receptors Lucian Del Fabbro a , Carlos Borges Filho a , Leandro Cattelan Souza a , Lucielli Savegnago b , Diego Alves c , Paulo Henrique Schneider d , Helena Domingues de Salles d , Cristiano R. Jesse a,n a Laborato ´rio de avaliac - ~ oes farmacolo ´ gicas e toxicolo ´ gicas aplicadas  as mole ´culas bioativas–LaftamBio Pampa–Universidade Federal do Pampa, CEP 97650-000 Itaqui, RS, Brazil b Centro de Desenvolvimento Tecnolo ´gico–CDTec, Unidade Biotecnologia, Universidade Federal de Pelotas–UFPel, CEP 96010-900 Pelotas, RS, Brazil c Laborato ´rio de Sı´ntese Orga ˆnica Limpa (LASOL), Universidade Federal de Pelotas, UFPel, CEP 96010-900 Pelotas, RS, Brazil d Instituto de Quı ´mica, Universidade Federal do Rio Grande do Sul, UFRGS - P.O. Box 15003, 9150-970 Porto Alegre, RS, Brazil article info Article history: Accepted 2 August 2012 Available online 8 August 2012 Keywords: Se-phenyl thiazolidine-4- carboselenoate Selenium Mechanical and thermal hyperalgesia Brachial plexus avulsion Cannabinoid receptors abstract In this study, we investigated the therapeutic effects of treatment with (R)-Se-phenyl thiazolidine-4-carboselenoate (Se-PTC), an organic selenium compound with antinociceptive properties, against mechanical and thermal hyperalgesia induced by brachial plexus avulsion (BPA), a neuropathic model in mice. The involvement of cannabinoid CB 1 and CB 2 receptors in the Se-PTC anti-hyperalgesic effect was also investigated. Se-PTC treatment at (25 and 50 mg/ kg, per oral, p.o.) lowered (BPA model) induced mechanical and thermal hyperalgesia in mice. Pretreatment with cannabinoid CB 1 (AM251; 1 mg/kg, intraperitoneally, i.p.), or CB 2 (AM630; 3 mg/kg, i.p.) receptor antagonists reverted the mechanical and thermal anti-hyperalgesic effect of Se-PTC (25 mg/kg) in the BPA model. Selective CB 1 (ACEA, 10 mg/kg, i.p.) and CB 2 (JWH-133, 10 mg/kg, i.p.) receptor agonists lowered mechanical and thermal hyperalgesia in the BPA model, and this effect was prevented by selective CB 1 and CB 2 receptor antagonists. Gabapentin (70 mg/kg, p.o.), positive control administration also lowered mechanical and thermal hyper- algesia in the BPA model. The results suggest that the mechanical and thermal hyperalgesia observed following BPA in mice is dependent on cannabinoid receptors. The results indicate that modulating cannabinoid receptors represent a valuable approach for the treatment of neuropathic pain. In conclusion, the results suggested that Se-PTC produces pronounced mechanical and thermal anti-hyperalgesic effects in neuropathic models in mice by modulating CB 1 and CB 2 receptors. Crown Copyright & 2012 Published by Elsevier B.V. All rights reserved. 0006-8993/$ - see front matter Crown Copyright & 2012 Published by Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.brainres.2012.08.008 Abbreviations: Se-PTC, (R)-Se-phenyl thiazolidine-4-carboselenoate; BPA, brachial plexus avulsion; p.o., per oral; i.p., intraperitoneally; i.pl., intra-plantar; MI, Maximum inhibition; AUC, area under curve; CCI, chronic constriction injury n Corresponding author. Fax: þ55 3433 1669. E-mail address: cristianoricardojesse@yahoo.com.br (C.R. Jesse). brainresearch 1475 (2012)31–36