MATERIALS AND METHODS: Antinociceptive activity of ethanol pomegranate extract was examined using three models of pain: the writhing test, the hot tail flick test and the plantar test. The ethanolic extract of pomegranate was administered by oral gavages in doses of (100,150 and 200mg/kg, p.o (orally)), for all the tests and compared with aspirin (100mg/kg, p.o.) which was considered as the standard drug. Phytochemical screening and HPLC analysis of the plant species was carried out.
RESULTS: In the writhing test, the index of pain inhibition (IPI) was 37% for ethanolic extract of pomegranate (200mg/kg, p.o.), and 59% for aspirin. In the hot tail flick test, the ethanolic extract of pomegranate (200mg/kg, p.o.), has shown significant analgesia reaching its peak at 60 min maximum possible analgesia (MPA), was 24.1% as compared with aspirin 37.5%. Hyperalgesia was successfully induced by the plantar test and the ethanol extract of pomegranate (100,150,200mg/kg, p.o.), reduced the hyperalgesia in a dose dependent manner comparable to aspirin at (100mg/kg, p.o.). HPLC analysis revealed the presence of gallic acid, ellagic acid and Punicalagins A&B.
CONCLUSION: The results demonstrated that ethanol pomegranate extract has an antinociceptive effect that may be related to the presence of identified phytochemicals.