Anagelsic and Anti-Inflammatory Activity of Ethanol Bark Extract of Vitellaria paradoxa in Wistar Albino Rats and Mice

Abstract

Vitellaria paradoxa is used for the treatment of several ailments in different parts of Nigeria including pain and inflammation. Vitellaria paradoxa, has been reported to possess a variety of pharmacological properties. This study was undertaken to investigate the analgesic and anti-inflammatory activity of Vitellaria paradoxa ethanol bark extract through different animal models.

The acute toxicity (LD50) of the extract was determined using Lorke’s method. The analgesic activities were evaluated by hot-plate and acetic acid induced writhing tests. The anti-inflammatory effect was assessed by rat paw oedema test.

In the hot-plate test, Vitellaria paradoxa significantly extend pain threshold when compared to control group. The inhibitory rates of writhes ranged from 6.6% to 28.1% in V. paradoxa-treated mice. Treatment with Vitellaria paradoxa especially at 100mg/kg and 50mg/kg could significantly increase (ranging from 38 – 101 minutes) the latent time to heat sensation. In carrageenan-induced oedema test, the inhibitory rates were 7.0% and 4.9% (p<0.05) at 180 minutes and 12 hours after administration of Vitellaria paradoxa (100mg/kg), respectively, while at an extract dose of 50mg/kg, the inhibitory percentages rates are 10.5% and 8.4% (p<0.05) at 120 minutes and 12 hours after administration of Vitellaria paradoxa (100mg/kg), respectively.

Results from the analgesic and anti-inflammatory studies of Vitellaria paradoxa ethanolic bark extracts showed significant effects exhibited in a dose dependent manner.