ANTINOCICEPTIVE EFFECTS AND TOXICITY OF FUMARIA PARVIFLORA LAM. IN MICE AND RATS

Abstract: In this study the antinoiciceptive and histopathological effects of the methanolic extract of fumaria parviflora Lam. in animal models was investigated. For this purpose, the antinociceptive effects of percolated and soxhlet extracts were evaluated in mice subjected to acute thermal (hot-plate) and persistent chemical (formalin) pain stimuli. Intraperitoneal (i.p.) injection of the percolated extract evoked significant antinociceptive effects at a dose of 100 mg/kg in the second phase of formalin test. The maximum antinociceptive effect was induced by the dose of 300 mg/kg that was significant in both phases of formalin test. Dose of 400 mg/kg of the percolated extract induced acute adverse effects such as diarrhea, polyurea, malasia and hyperventilation in mice. Soxhlet extract of F. parviflora (300 mg/kg, i.p.) also showed significant effects in the both phases of formalin test. The most effective dose of the percolated extract as well as the soxhlet extracts (300 mg/kg, i.p.) were evaluated in hot plate test. The results showed that only percolated extract had significant antinociceptive effect in hot-plate. Pretreatment of mice with naloxane, an opioid antagonist, did not change antinociceptive effect of percolated extract in formalin test, but in hot-plate it increased extract’s effect after the first 15 minutes. In histopathological evaluation of liver, toxic dose of percolated extract (400 mg/kg) caused degeneration, necrosis and regeneration of hepatic cells. The study of ulcerogenic effects of oral percolated extract on stomach in rats showed that this adverse effect was significantly lower in comparison with the same dose of indomethacin. These results showed F. parviflora is relatively safe for use and it is a good candidate for further studies to determine its effective and probable toxic compound(s).