Antinociceptive effect of <i>Pleurotus ostreatus</i> (Oyster Mushroom) Aqueous Extracts in <i>Rattus norvegicus</i> (Albino Rats)

Abstract

Antinociceptive is reducing sensitivity to painful stimuli for the individual. The objective of this study was to evaluate the antinociceptive potentials of graded doses of Pleurotus ostreatus (Oyster Mushroom) aqueous extract in Rattus norvegicus (Albino Rats) and its chemical pattern by comparing it with a standard drug and a control using the hot water based flick tail test. Thirty five adult rats of both sexes were used for the experiment which, were divided into five groups of seven rats per group. Group one was used as the control (with 1ml normal saline), while groups two, three and four were treated with 100, 200 and 400 mg/kg of Pleurotus ostreatus aqueous extracts and group five treated with 15 mg/kg Aspirin (a standard drug) as positive control. Hot water at 55⁰C was used to determine the nociceptive responses of the animals to detect anti-nociceptive effects of Pleurotus ostreatus extracts as compared to the control in hot water inflicted pain. The results suggested that Pleurotus ostreatus aqueous extract exhibits antinociceptive properties against thermal stimulus at 55⁰C. The diversity of individual animals’ pain tolerance threshold when immersed in hot water was also observed during the experiment. However, the extract indicated a high degree of anti-nociceptive effect at 30, 60, 90 and 120 minutes post treatment period, with a progressively longer threshold time for pain sensitivity. It was also found that at 90 minute period, the control portrayed a relatively short response time.

KEY WORDS: Anti-nociceptive, threshold pain, Pleurotus ostreatus, hot water test flick tail.