Annafi Olajide S, Umukoro Solomon, Eduviere Anthony T
Department of Pharmacology and Therapeutics, University of Ibadan, Ibadan, Nigeria.
Sci Pharm. 2014 Mar 24;82(3):643-54. doi: 10.3797/scipharm.1310-22. Print 2014 Jul-Sep.
Methyl jasmonate (MJ) is one of the most well-studied plant stress hormones belonging to the jasmonate family. Previous studies have shown that MJ potentiated pentobarbitone sleeping time and enhanced GABA-mediated inhibitory neurotransmission, suggesting potential benefits in disorders associated with hyperactivity of the brain. This study was carried out to evaluate whether MJ has anticonvulsant and anxiolytic properties in mice. The anticonvulsant effect was assessed based on the prevention of tonic-clonic seizures induced by chemoconvulsant agents in mice. The anxiolytic property was evaluated utilizing the elevated plus maze (EPM) and light/dark transition paradigms. The effect of MJ on spontaneous locomotor activity (SMA) was also assessed. Mice received intraperitoneal (i.p.) injections of MJ 30 min before the tests were carried out and diazepam (2 mg/kg, i.p.) was used as the reference drug. MJ (50-400 mg/kg) did not protect the mice against tonic-clonic convulsions induced by picrotoxin (10 mg/kg, i.p.) or strychnine (3 mg/kg, i.p.). However, MJ (100, 200, and 400 mg/kg) offered 20, 60, and 100% protection against pentylenetetrazole (100 mg/kg, i.p.)-induced convulsions. In a similar manner to diazepam (2 mg/kg), MJ (400 mg/kg) produced a marked sedative effect as shown by decreases in the number of lines crossed and the duration of ambulation in the open field test. In contrast to diazepam (2 mg/kg), MJ (5-50 mg/kg) did not show anxiolytic effects in the EPM and light/dark transition paradigms. These findings suggest that methyl jasmonate at high doses possessed anticonvulsant properties in the pentylenetetrazole animal model of epilepsy, but did not produce anxiolytic activity in mice.
茉莉酸甲酯(MJ)是茉莉酸家族中研究最为深入的植物应激激素之一。先前的研究表明,MJ可延长戊巴比妥睡眠时间,并增强γ-氨基丁酸(GABA)介导的抑制性神经传递,提示其在与大脑活动亢进相关的疾病中可能具有潜在益处。本研究旨在评估MJ在小鼠中是否具有抗惊厥和抗焦虑特性。基于预防化学惊厥剂诱导的小鼠强直性阵挛性惊厥来评估抗惊厥作用。利用高架十字迷宫(EPM)和明暗转换范式评估抗焦虑特性。还评估了MJ对自发运动活动(SMA)的影响。在进行测试前30分钟,小鼠腹腔注射MJ,地西泮(2毫克/千克,腹腔注射)用作参考药物。MJ(50 - 400毫克/千克)不能保护小鼠免受印防己毒素(10毫克/千克,腹腔注射)或士的宁(3毫克/千克,腹腔注射)诱导的强直性阵挛性惊厥。然而,MJ(100、200和400毫克/千克)对戊四氮(100毫克/千克,腹腔注射)诱导的惊厥提供了20%、60%和100%的保护。与地西泮(2毫克/千克)类似,MJ(400毫克/千克)产生了明显的镇静作用,如旷场试验中穿越的线条数量和行走持续时间减少所示。与地西泮(2毫克/千克)不同,MJ(5 - 50毫克/千克)在EPM和明暗转换范式中未表现出抗焦虑作用。这些发现表明,高剂量的茉莉酸甲酯在癫痫的戊四氮动物模型中具有抗惊厥特性,但在小鼠中未产生抗焦虑活性。