Abstract:
The aim of the study was to ascertain the analgesic properties of Mondia whytei
roots and to isolate and characterize the active constituents. Bioactivity guided
fractionation of the chloroform root extract yielded stigmasterol and 9-hexacosene.
Stigmasterol (15 mg/kg) and 9-hexacosene (30 mg/kg) significantly (p<0.05)
inhibited chemical nociception induced by intraperitoneal acetic acid. Stigmasterol
(7.5, 15, 30 and 100 mg/kg) dose dependently reduced the time spent in pain behavior
in both the early and late phases of the formalin test. 9-hexacosene dose
dependently caused significant (p<0.001) antinociceptive effect on the late phase of
the formalin test. Co-administration of naloxone failed to antagonize the analgesic
activity of stigmasterol and 9-hexacosene in the formalin test. We concluded that
both stigmasterol and 9-hexacosene possess potential analgesic effects which are
most likely mediated by their anti-inflammatory activities rather than through
opioid receptor system.
