Antinociceptive effect of Ferula assa-foetida oleo-gum-resin in mice.

Ferula assa-foetida L. is distributed throughout central Asia and Mediterranean area and grows wildly in Iran and Afghanistan. Asafoetida is an oleo-gum-resin that is the exudates of the roots of Ferula assa-foetida and some other Ferula species. In Iranian traditional medicine, asafoetida is considered to be sedative, analgesic, carminative, antispasmodic, diuretic, antihelmintic, emmenagogue and expectorant. The aim of this study was to evaluate the antinociceptive effect of asafoetida in mice. The analgesic activity of asafoetida (25, 50 and 100 mg/kg) was compared with that of sodium diclofenac (30 mg/kg) or morphine sulfate (8 mg/kg) by using hot plate and acetic acid induced writhing tests. In hot plate test, the percentage of maximum possible effect (%MPE) against the thermal stimulus at 15 min post treatment time point for all doses of asafoetida was significantly greater than the control group. The number of writhes in all three doses of asafoetida was significantly less than the control group. GraphPad Prism 5 software was used to analyze the behavioral responses. Data were analyzed using repeated measure one-way ANOVA and P<0.05 was considered as the significant level. According to our findings, asafoetida exhibited a significant antinociceptive effect on chronic and acute pain in mice. These effects probably involve central opioid pathways and peripheral anti-inflammatory action.