乌灵菌粉抗大鼠戊四唑诱导癫痫的作用

Effects of Wuling mycelia on pentylenetetrazole-induced epilepsy in rats

目的:研究乌灵菌粉对大鼠戊四唑的癫痫点燃过程和点燃后学习能力的影响及其可能的机制。方法:将SD大鼠随机分为4组:戊四唑点燃模型组(模型对照组),低剂量乌灵菌粉组(0.3 g.kg-1),高剂量乌灵菌粉组(0.6 g.kg-1)和空白对照组。各组大鼠隔日腹腔注射亚惊厥剂量戊四唑(35 mg.kg-1),空白对照组注射生理盐水,共12次。乌灵菌粉于每次戊四唑注射前30 min灌胃。采用放射状八臂迷宫(四臂放食物)测试大鼠学习能力。化学荧光法测定大鼠脑内组胺含量。结果:(1)与模型对照组相比,低剂量乌灵菌粉组第7次注射戊四唑后发作级别显著降低,第6次注射戊四唑后肌阵挛潜伏期明显延长,第7次注射戊四唑后癫痫泛化潜伏期明显延长(P<0.05);高剂量乌灵菌粉组第6、7和8次注射戊四唑后癫痫发作级别明显降低,第8和9次注射戊四唑后肌阵挛潜伏期显著延长,第6次注射戊四唑后癫痫泛化潜伏期明显延长(P<0.05);(2)与空白对照组相比,模型对照组在放射状八臂迷宫训练3天后工作记忆和参考记忆错误次数均明显增加(P<0.05),乌灵菌粉部分逆转了这种戊四唑点燃癫痫诱发的学习能力受损;(3)模型对照组海马、皮层、丘脑和下丘脑组胺含量较空白对照组明显下降(P<0.05),低剂量乌灵菌粉组海马、高剂量乌灵菌粉组海马、丘脑和下丘脑组胺含量较模型对照组上升(P<0.05)。结论:乌灵菌粉延缓大鼠戊四唑癫痫点燃的形成过程,改善癫痫大鼠的学习能力,增强脑内组胺能神经可能是其作用机制之一。

Objective： To investigate the effects and mechanisms of Wuling mycelia on seizure development and learning ability induced by pentylenetetrazole-kindling epilepsy in rats.Methods： SD rats were randomly divided into four groups： pentylenetetrazole-kindling model group（model group）,low dose Wuling mycelia（0.3 g·kg-1） group（LD-WM group）,high dose Wuling mycelia（0.6 g·kg-1） group（HD-WM group） and control group.The rats were intraperitoneal injected with a subconvulsive dose（35 mg·kg-1） of pentylenetetrazole（saline in control group） every 48 h for 12 times.Wuling mycelia was intragastrically applied 30 min before pentylenetetrazole injection.An 8-arm radial maze（4 arms baited） was used to measure the learning ability.Histamine was measured by chemical fluorometric enzyme immunoassay.Results： Compared with the model group,the kindling stage of LD-WM group degraded significantly after 7th injection,the latency to the onset of myoclonic jerks（LTMJ） and the latency to the onset of generalized seizures（LTGS） prolonged after the 6th and 7th injection,respectively（P0.05）.The kindling stage of HD-WM group also degraded markedly after the 6th to 8th injection,and the LTMJ and the LTGS extended after the 8th to 9th and 6th injection,respectively（P0.05）.Compared with the control group,the frequency of working memory error（WME） and reference memory error（RME） of the model group in the 8-arm radial maze increased through 3-d training（P0.05）.The memory tests showed that the impairment induced by pentylenetetrazole was partially reversed by Wuling mycelia.Compared with the control group,brain histamine contents（hippocampus,cortex,thalamus and hypothalamus） were significantly lower in model group（P0.05）.But compared with the model group,hippocampal histamine contents in LD-WM group and hippocampal,thalamic and hypothalamic histamine contents in HD-WM group were elevated（P0.05）.Conclusion： Wuling mycelia can delay the kindling and ameliorate the ability of learning in rats with pentylenetetrazole-induced epilepsy and the enhancement of neuronal histamine activity may be one of possible mechanisms.