title: Analgesic properties of extracts and fractions from Erythrina crista-galli (Fabaceae) leaves.
abstract: The present study describes the analgesic activity of extracts and some fractions obtained from Erythrina crista-galli leaves in different in vivo analgesic models, using mice as experimental animals. The results showed that extract E(2) was the most active, inhibiting 48% of the abdominal constrictions when evaluated against the writhing test at 10 mg kg(-1), intraperitoneal. It also caused dose-dependent inhibition in the same model, with a calculated ID(50) value and respective confidence interval of 10 (9-14) mg kg(-1), and was more potent than reference drugs. Administered orally, E(2) caused potent antinociceptive action, with a calculated ID(50) value of 35 (26-47) mg kg(-1). The fractions F(1) and F(2) obtained from E(2) were evaluated against the writhing test at 10 mg kg(-1), causing inhibitions of 41 and 88%, respectively. The most active fraction, F(2), presented ID(50) calculated value of 3 (2-4) mg kg(-1), being about 7-fold more active than the reference drugs (acetyl salicylic acid and acetaminophen). In the formalin test, F(2) inhibited both phases of pain (44%, first phase; 58%, second phase). However, in contrast to the results observed for E(2), it was not active against the hot-plate test. The phytochemical results showed that at least four main components are present in F(2), which show a positive reaction of terpenes with TLC spray reagents.
authors.affiliation: Núcleo de Investigações Químico-Farmacêuticas (NIQFAR)/CCS, Universidade do Vale do Itajaí (UNIVALI), Itajaí, SC, Brazil. cechinel@univali.br
authors.forename: Luiz G O
authors.initials: LG
authors.lastname: Fischer
authors.forename: Rafael
authors.initials: R
authors.lastname: Leitão
authors.forename: Silvia R
authors.initials: SR
authors.lastname: Etcheverry
authors.forename: Fãtima
authors.initials: F
authors.lastname: de Campos-Buzzi
authors.forename: Alvaro A
authors.initials: AA
authors.lastname: Vãzquez
authors.forename: Horácio A
authors.initials: HA
authors.lastname: Heinzen
authors.forename: V
authors.initials: V
authors.lastname: Cechinel Filho
mesh_terms: D018712:Analgesics, Non-Narcotic / Q000737:chemistry / Q000494:pharmacology*; D000818:Animals; D004895:Erythrina / Q000737:chemistry*; D008297:Male; D051379:Mice; D010147:Pain Measurement / Q000187:drug effects*; D035261:Plant Components, Aerial / Q000737:chemistry; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D010946:Plants, Medicinal / Q000737:chemistry; D011897:Random Allocation
chemical_list: D018712:Analgesics, Non-Narcotic; D010936:Plant Extracts