Antinociceptive activity of Hypericum caprifoliatum and Hypericum polyanthemum (Guttiferae)
Rev. bras. pesqui. méd. biol
; Braz. j. med. biol. res;36(5): 631-634, May 2003. tab
Article
em En
| LILACS
| ID: lil-331452
Biblioteca responsável:
BR1.1
ABSTRACT
The aim of the present study was to assess the analgesic activity of the aerial parts of two Hypericum species native to Southern Brazil, H. caprifoliatum and H. polyanthemum. The antinociceptive effect of the H. polyanthemum cyclohexane extract (POL; 180 mg/kg) and of the H. caprifoliatum methanol (MET) and cyclohexane (CH) extracts (90 mg/kg) was evaluated in the hot-plate (ip and po) and writhing (po) tests using male Swiss CF1 mice weighing 22-27 g (N = 10 per group). All extracts displayed antinociceptive effects in the hot-plate test (MET ip = 48 percent, MET po = 39 percent, CH ip = 27 percent, CH po = 50 percent, POL ip = 74 percent, and POL po = 49 percent compared to control). Pretreatment with naloxone (2.5 mg/kg, sc) abolished the effects of CH and POL, and partially prevented the analgesia induced by MET administered by the ip (but not by the po) route. POL and CH (po) significantly reduced the number of writhes induced by acetic acid, while MET was ineffective in this regard. We conclude that the antinociceptive effects of the H. caprifoliatum (CH) and H. polyanthemum (POL) hexane extracts seem to be mediated by the opioid system. Moreover, the antinociceptive activity of the H. caprifoliatum MET extract seems to depend on at least two chemical substances (or groups of substances) with distinct pharmacokinetic profiles and mechanisms of action. Only the naloxone-insensitive component of MET activity showed good bioavailability following oral administration
Texto completo:
1
Coleções:
01-internacional
Base de dados:
LILACS
Assunto principal:
Plantas Medicinais
/
Extratos Vegetais
/
Limiar da Dor
/
Hypericum
/
Analgésicos
Limite:
Animals
Idioma:
En
Revista:
Braz. j. med. biol. res
/
Rev. bras. pesqui. méd. biol
Assunto da revista:
BIOLOGIA
/
MEDICINA
Ano de publicação:
2003
Tipo de documento:
Article
/
Congress and conference
País de afiliação:
Brasil
País de publicação:
Brasil