title: Peripheral 5-HT1B and 5-HT2A receptors mediate the nociceptive response induced by 5-hydroxytryptamine in mice.
abstract: While the role of 5-hydroxytryptamine (5-HT, serotonin) in the nociceptive processing has been widely investigated in the central nervous system, information regarding its role in peripheral tissues is still lacking. Noteworthy, 5-HT induces phenotypic changes of nociceptors and peripheral injection induces pain in humans and nociceptive response in rodents. However, local receptors involved in 5-HT effects are not well characterized. Thus, we aimed to investigate the role of 5-HT and some of its receptors in the peripheral nociceptive processing in mice. Intraplantar injection of 5-HT (10, 20 or 40 μg) into the hind-paw of mice induced paw licking behavior, which was inhibited by previous intraplantar treatment with cyproheptadine (5-HT(1) and 5-HT(2) antagonist; 0.5 or 5 μg), mianserin (5-HT(2) and 5-HT(6) antagonist; 0.1 μg), isamoltane (5-HT(1B) antagonist; 0.5 or 5 μg) and ketanserin (5-HT(2A) antagonist; 0.1 or 1 μg), but not by BRL 15572 (5-HT(1D) antagonist; 1 or 10 μg), ondansetron (5-HT(3) antagonist; 1, 5, 10 or 20 μg) and SB 269970 (5-HT(7) antagonist; 2.5 and 25 μg). Altogether, these results indicate the local involvement of 5-HT(1), 5-HT(2) and 5-HT(6), especially 5-HT(1B) and 5-HT(2A), in the nociceptive response induced by 5-HT in mice, thus contributing to a better understanding of 5-HT role in the peripheral nociceptive processing. In addition, they also point to important species differences and the need of a wide evaluation of the peripheral nociceptive processing in mice as these animals have been increasingly used in studies investigating the cellular and molecular mechanisms mediating the nociceptive response.
authors.affiliation: Laboratório de Farmacologia, Faculdade de Farmácia, Universidade Federal de Minas Gerais, Avenida Antônio Carlos 6627, 31270-901 Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Elias B
authors.initials: EB
authors.lastname: Nascimento
authors.forename: João Gabriel T
authors.initials: JG
authors.lastname: Seniuk
authors.forename: Adriana M
authors.initials: AM
authors.lastname: Godin
authors.forename: Wallace C
authors.initials: WC
authors.lastname: Ferreira
authors.forename: Marcela B
authors.initials: MB
authors.lastname: Dutra
authors.forename: Antônio Carlos P
authors.initials: AC
authors.lastname: Oliveira
authors.forename: Leandro F S
authors.initials: LF
authors.lastname: Bastos
authors.forename: Bernd L
authors.initials: BL
authors.lastname: Fiebich
authors.forename: Márcio M
authors.initials: MM
authors.lastname: Coelho
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D008297:Male; D051379:Mice; D009619:Nociceptors / Q000187:drug effects*; D010146:Pain / Q000523:psychology*; D044302:Receptor, Serotonin, 5-HT1B / Q000187:drug effects*; D044402:Receptor, Serotonin, 5-HT2A / Q000187:drug effects*; D011985:Receptors, Serotonin / Q000187:drug effects; D012701:Serotonin / Q000494:pharmacology*; D012702:Serotonin Antagonists / Q000494:pharmacology
chemical_list: D044302:Receptor, Serotonin, 5-HT1B; D044402:Receptor, Serotonin, 5-HT2A; D011985:Receptors, Serotonin; D012702:Serotonin Antagonists; C104425:serotonin 7 receptor; D012701:Serotonin