Anti-nociceptive and anti-inflammatory properties of the ethanolic extract of Lagenaria breviflora whole fruit in rat and mice.

Abstract

The present study was conducted to evaluate the anti-nociceptive and anti-inflammatory properties of an ethanol extract of whole fruit of Lagenaria breviflora (LB) in rat and mice. Analgesic activity was measured by hot plate, formalin-induced paw licking, and acetic acid-induced abdominal writhing tests, while anti-inflammatory activity was determined by inhibition of carrageenan-induced paw oedema. Extract-treated animals exhibited significantly (P<0.05) higher pain threshold, lower number of licking of paws in response to formalin-induced irritation and writhing movements in response to acetic acid-induced writhing movement. There was significant (P<0.05) inhibition of carrageenan-induced paw oedema in rats pre-treated with the extract (50, 100, 200mg/kg) by 6.4%, 27.5%, 55.9% respectively. Analgesic effect of the extract (50, 100, 200mg/kg) in hot plate test was observable within 30 minutes of administration with maximum effect obtainable 90 minutes post-administration. Also, the effect of the extract (50, 100 and 200mg/kg) was dose dependent in both the early (88.17±6.21, 80.33±3.49 and 72.33±5.16) and late (72.50±3.95, 53.83±3.96 and 35.83±3.78) phases of formalin-induced paw licking, and in acetic acid-induced writhing with inhibition of 26.8%, 48.1% and 58.1% respectively. Its effect was comparable especially at 200mg/kg body weight to those of diclofenac, indomethacin and ibuprofen. It could be suggested from the findings of this experiment that the extract may be mediating its action as a central analgesic agent but the peripheral analgesic effect was preponderant based on its outcome from the pain models.