Investigation of the Involvement of the Endocannabinoid System in TENS-Induced Antinociception

Autor(es):Mostrar menos -

de Oliveira, Herick Ulisses ^[1] ; dos Santos, Rafaela Silva ^[1] ; Silva Malta, Iago Henrique ^[1] ; Pinho, Jose Phellipe ^[2] ; Santos Almeida, Ana Flavia ^[2] ; Sorgi, Carlos Arterio ^[3] ; Ferranti Peti, Ana Paula ^[3] ; Xavier, Gabriela Santos ^[1] ; dos Reis, Luciana Maria ^[1] ; Faccioli, Lucia Helena ^[3] ; Cruz, Jader dos Santos ^[2] ; Ferreira, Enio ^[4] ; Galdino, Giovane ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Alfenas, Sci Motr Inst, Jovino Fernandes Sales Ave 2600, BR-37130000 Alfenas - Brazil

^[2] Univ Fed Minas Gerais, Dept Physiol, Belo Horizonte, MG - Brazil

^[3] Univ Sao Paulo, Fac Pharmaceut Sci Ribeirao Preto, Sao Paulo - Brazil

^[4] Univ Fed Minas Gerais, Dept Pathol, Belo Horizonte, MG - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF PAIN; v. 21, n. 7-8, p. 820-835, JUL-AUG 2020.
• Citações Web of Science: 0

Resumo

Transcutaneous electrical nerve stimulation (TENS) promotes antinociception by activating the descending pain modulation pathway and consequently releasing endogenous analgesic substances. In addition, recent studies have shown that the endocannabinoid system controls pain. Thus, the present study investigated the involvement of the endocannabinoid system in TENS-induced antinociception of cancer pain using a cancer pain model induced by intraplantar (i.pl.) injections of Ehrlich tumor cells in male Swiss mice. Low- and high-frequency TENS was applied for 20 minutes to the mice's paws, and to investigate the involvement of the endocannabinoid system were used the N(peperidin-1-yl)-5-(4-iodophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pi tazole-3-carboixamide (AM251), a cannabinoid CB1 receptor antagonist and (5Z,8Z,11Z,14Z)-5,8,11,14-eicosatetraenyl-methylester phosphonofluoridic acid (MAFP), an inhibitor of the endocannabinoid metabolizing enzyme fatty acid amide hydrolase, injected by via i.pl., intrathecal (i.t.), and intradorsolateral periaqueductal gray matter (i.dl. PAG). Furthermore, liquid chromatography-tandem mass spectrometry, western blot, and immunofluorescence assays were used to evaluate the endocannabinoid anandamide levels, cannabinoid CB1 receptor protein levels, and cannabinoid CB1 receptor immunoreactivity, respectively. Low- and high-frequency TENS reduced the mechanical allodynia induced by Ehrlich tumor cells and this effect was reversed by AM251 and potentiated by MAFP at the peripheral and central levels. In addition, TENS increased the endocannabinoid anandamide levels and the cannabinoid CB1 receptor protein levels and immunoreactivity in the paw, spinal cord, and dorsolateral periaqueductal gray matter. These results suggest that low- and high-frequency TENS is effective in controlling cancer pain, and the endocannabinoid system is involved in this effect at both the peripheral and central levels. Perspective: TENS is a nonpharmacological strategy that may be used to control cancer pain. Identification of a new mechanism involved in its analgesic effect could lead to the development of clinical studies as well as an increase in its application, lessening the need for pharmacological treatments. (C) 2019 by United States Association for the Study of Pain, Inc. (AU)

• Processo FAPESP: 14/07125-6 - Novos aspectos funcionais dos eicosanóides
• Beneficiário: Lúcia Helena Faccioli
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 15/00658-1 - Novos aspectos funcionais dos eicosanóides
• Beneficiário: Lúcia Helena Faccioli
• Modalidade de apoio: Auxílio à Pesquisa - Programa Equipamentos Multiusuários