Anti-Inflammatory and Analgesic Evaluation of Parinari curatellifolia Methanol Leaf Extract on Albino Rats

Aim: This research was designed to evaluate the anti-inflammatory and analgesic activities of Parinari curatellifolia methanol leaf extract in albino rats.

Methodology: Phytochemical screening was carried out using standard methods. Anti-inflammatory activity of the extract was done using egg albumin and formalin induced hind paw edema model. Analgesic effect was evaluated using hot plate induced pain and acetic acid induced writhing test. For each model twenty (20) rats were used, divided into five (5) groups of four (4) rats each.

Results: Parinari curatellifolia revealed the presence of alkaloids, flavonoids, tannins and phenols while steroids, anthraquinone, terpenoids and glycoside were not detected. For the egg albumin induced inflammation, the group treated with the standard drug (indomethacin) and the group that received the highest dose of the extract were significantly lower (P<0.05) than all the other groups with percentage inhibitions at 25.56% and 24.44% respectively there was no significant difference (P>0.05). For the formalin induced anti-inflammatory activity, at the 1st hour, the normal control group had its paw volume significantly different (P<0.05) from the treated groups. This trend was observed at the 2nd, 3rd and 4th hour. The hot plate method results revealed significant increased (P<0.05) in the analgesic activity of PCMLE at 400mg/kg body weight and the drug treated group when the control was compared with the treated groups with percentage inhibition of 34.32% and 52.94% respectively. The acetic acid induced writhing test revealed that the extract at the three doses of 100, 200 and 400 mg/kg body weight, showed a significant (P<0.05) percentage inhibition of 32.31%, 36.92% and 47.69%, respectively compared to negative control.

Conclusion: This justifies the use of Parinari curatellifolia locally in the management of pain and inflammation.