Analgesic Activity of the Extract of Aerial Parts of Colza (Brassica Napus) in Mice

Abstract

BACKGROUND AND OBJECTIVE: It has been reported that Cruciferous family plants such as Brassica napus (Colza) are abundant sources of flavonoid compounds that involve in prostaglandin synthesis and may show analgesic and anti-inflammatory effects. The purpose of this study was to investigate the analgesic effect of hydroalcoholic extract of aerial parts of Colza in comparison with morphine, with or without naloxone in mice. METHODS: The male mice weighing 18-26 g were divided into experimental groups (6 mice in each group) and received i.p. injections of 50, 100, 250 and 500 mg/kg of the hydroalcoholic extract of colza and morphine with or without naloxone, respectively. Normal saline was used as control. The hot-plate test was performed to evaluate the analgesic effects of all treatments and pain latency was measured at 15, 30, 45, 60, 75, and 90 minutes after injection of the drugs. FINDINGS: Pain tolerance of the mice receiving various doses of colza extract was significantly increased compared to the control. Moreover, simultaneous injection of morphine (20 mg/kg) and colza extract (250 mg/kg) increased pain tolerance compared to morphine alone. Also, simultaneous injection of colza extract and morphine at 10 minutes after naloxone (1 mg/kg), increased analgesia in the animals. The highest analgesia was observed after treatment with morphine and colza extract (250 mg/kg) at 30 minutes after the injection (32±2 seconds). CONCLUSION: According to the results, the hydroalcoholic extract of the aerial parts of colza induced analgesia In mice during the hot-plate test. This effect may be attributed to the presence of flavonoid compounds in the extract, which confirms the analgesic properties of colza