اثر ضددردي و مكانيسم احتمالي عصاره متانولي گياه سورنجان كرماني در موش سوري

The Analgesic Effect and Possible Mechanism of Colchicum Szovitsii Methanolic Extract in Mouse

Background: Some of plants are used as analgesic in traditional medicine. The aim of this investigation was to evaluate the analgesic effects of colchicum szovitsii Fisch and C.A. Mey that has been used traditionally to relieve the pain. Materials and Methods: The plant specimen was collected from Jupar, and then identified and nominated by a botanist. The dried bulbs of the plant was powdered and extracted by Percolated method and then concentrated by rotatory evaporator and oven. Different doses of methanolic extract of the plant was injected into male albino mice (20-25g) and its analgesic effect was evaluated by Hot-plate and formalin test. Results: The results showed that all doses of extract, induce significant analgesia (p<0.01) in l lot plate test. The dose of 200 mg/kg of extract, induced toxic effect such as diarrhea and lethargy in mice. The results showed that, the doses of 50 and 100 mg/kg of extract, induced significant antinociception compared to the control group in all time intervals after 10-15 minutes in formalin test (p<0.05, p<0.01). There was not significant differences between the analgesic effect of the most effective dose of extract (100 mg/kg), ASA(300 mg/kg) and morphine (2.5 mg/kg), in second phase of formalin test. The analgesic effect of the extract was lower than morphine (p<0.01) 15 am 30 min after injection in Hot plate test. The analgesic effect of extract was lower than ASA 15 min after injection (p<0.01) but was higher than ASA 60 min after injection(p<0.05). Pretreatment of animals with naloxone 4mg/kg, subcutaneously, five minute before extract injection, decreased the analgesia induced by extract in all times of hot-plate test (p<0.01) except 15 min. Naloxone decreased the analgesic effect of extract in formalin test(p<0.01), except in time intervals between 5-10, 10-15 and 25-30 min. Conclusion: The results show that, the methanolic extract of colchicum szovitsii has a significant analgesic effect in formalin and Hot plate test and the opioid receptor may be involved in the analgesic effect of this plant. The results of this investigation could be used for more studies to access a better results.