title: Antinociceptive effects of a chloroform extract and the alkaloid dicentrine isolated from fruits of Ocotea puberula.
abstract: The present work describes the chemical characterization of a chloroform fraction (CF) obtained from an extract of Ocotea puberula (Lauraceae) fruits, and preliminary antinociceptive analysis of CF and the alkaloid dicentrine, isolated from this fraction. CF (30-300 mg/kg, p. o.) caused dose-related inhibition of abdominal constrictions caused by acetic acid and also inhibited both phases of formalin-induced nociception. However, hexane or ethyl acetate fractions did not produce any effect. Antinociception caused by CF (100 mg/kg, p. o.) in the acetic acid test was not affected either by caffeine, an adenosine receptor antagonist, or by naloxone, an opioid receptor antagonist, and neither was associated with nonspecific effects such as muscle relaxation or sedation. Furthermore, dicentrine (30-300 mg/kg, p. o.) produced dose-related inhibition of acetic acid-induced pain without causing changes in the motor performance of mice. The results show, for the first time, that CF from Ocotea puberula fruits produced marked antinociception in different models of chemical pain, and this effect appears to be, at least in part, due to the presence of dicentrine. The mechanism by which CF and the alkaloid produced antinociception still remains unclear, but the adenosinergic or opioid system seems unlikely to be involved in this action.
authors: Departamento de Farmácia, Setor de Ciências da Saúde, Universidade Federal do Paraná, Curitiba, PR, Brazil.
authors: Deise Prehs
authors: DP
authors: Montrucchio
authors: Obdulio Gomes
authors: OG
authors: Miguel
authors: Sandra Maria Warumby
authors: SM
authors: Zanin
authors: Gabriel Araujo
authors: GA
authors: da Silva
authors: Alcíbia Maia
authors: AM
authors: Cardozo
authors: Adair Roberto Soares
authors: AR
authors: Santos
mesh_terms: D019342:Acetic Acid / Q000494:pharmacology; D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D000701:Analgesics, Opioid / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D001060:Aporphines / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D002725:Chloroform; D004305:Dose-Response Relationship, Drug; D005557:Formaldehyde / Q000494:pharmacology; D005638:Fruit / Q000737:chemistry; D008297:Male; D051379:Mice; D015394:Molecular Structure; D059226:Nociceptive Pain / Q000139:chemically induced; D027444:Ocotea / Q000737:chemistry*; D010146:Pain / Q000139:chemically induced; D010147:Pain Measurement / Q000187:drug effects; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*
chemical_list: D000470:Alkaloids; D000701:Analgesics, Opioid; D001060:Aporphines; D010936:Plant Extracts; D005557:Formaldehyde; D002725:Chloroform; C067342:dicentrine; D019342:Acetic Acid