title: B vitamins induce an antinociceptive effect in the acetic acid and formaldehyde models of nociception in mice.
abstract: The effect of some B vitamins in chemical and thermal models of nociception in mice was investigated. The association thiamine/pyridoxine/cyanocobalamin (TPC, 20-200 mg/kg, i.p. or per os), thiamine, pyridoxine (50-200 mg/kg, i.p.) or riboflavin (3-100 mg/kg, i.p) induced an antinociceptive effect, not changed by naloxone (10 mg/kg, i.p.), in the acetic acid writhing model. Treatment for 7 days with thiamine/pyridoxine/cyanocobalamin (100 or 200 mg/kg, i.p.), thiamine (50 or 100 mg/kg) or pyridoxine (50 or 100 mg/kg) or acute treatment with riboflavin (6 or 12 mg/kg, i.p) inhibited the nociceptive response induced by formaldehyde. The B vitamins did not inhibit the nociceptive response in the hot-plate model. Both 7-day thiamine/pyridoxine/cyanocobalamin (100 mg/kg, i.p.) or acute riboflavin (25 or 50 mg/kg, i.p.) treatment partially reduced formaldehyde-induced hindpaw oedema. The B vitamins antinociceptive effect may involve inhibition of the synthesis and/or action of inflammatory mediators since it was not observed in the hot-plate model, was not reversed by naloxone, only the second phase of the formaldehyde-induced nociceptive response was inhibited, and formaldehyde-induced hindpaw oedema was reduced.
authors.affiliation: Laboratory of Pharmacology, Faculty of Pharmacy, Federal University of Minas Gerais, Avenida Olegário Maciel 2360, 30180-112 MG, Belo Horizonte, Brazil.
authors.forename: D S
authors.initials: DS
authors.lastname: França
authors.forename: A L
authors.initials: AL
authors.lastname: Souza
authors.forename: K R
authors.initials: KR
authors.lastname: Almeida
authors.forename: S S
authors.initials: SS
authors.lastname: Dolabella
authors.forename: C
authors.initials: C
authors.lastname: Martinelli
authors.forename: M M
authors.initials: MM
authors.lastname: Coelho
mesh_terms: D019342:Acetic Acid; D000818:Animals; D003250:Constriction; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004487:Edema / Q000139:chemically induced / Q000517:prevention & control; D005557:Formaldehyde; D006614:Hindlimb; D007274:Injections, Intraperitoneal; D007279:Injections, Subcutaneous; D008297:Male; D051379:Mice; D009043:Motor Activity / Q000187:drug effects; D009270:Naloxone / Q000494:pharmacology; D009619:Nociceptors / Q000187:drug effects*; D010146:Pain / Q000139:chemically induced / Q000503:physiopathology / Q000517:prevention & control*; D010147:Pain Measurement / Q000379:methods; D011736:Pyridoxine / Q000494:pharmacology; D012256:Riboflavin / Q000494:pharmacology; D013831:Thiamine / Q000494:pharmacology; D014805:Vitamin B 12 / Q000494:pharmacology; D014803:Vitamin B Complex / Q000494:pharmacology*
chemical_list: D014803:Vitamin B Complex; D005557:Formaldehyde; D009270:Naloxone; D011736:Pyridoxine; D014805:Vitamin B 12; D019342:Acetic Acid; D012256:Riboflavin; D013831:Thiamine