腺苷A2A受体拮抗剂对大鼠氯化锂-毛果芸香碱所致癫痫模型的影响

Effect of adenosine A2A receptor antagonist on a rat model of lithium-pilocarpine epilepsy

目的研究腺苷A2A受体阻断剂对大鼠氯化锂-毛果芸香碱癫痫持续状态(SE)模型的影响。方法选取50只WD大鼠随机分为对照组、模型组及A2A受体阻断剂组。模型组采用氯化锂-毛果芸香碱腹腔注射复制癫痫模型,A2 A受体阻断剂组在氯化锂-毛果芸香碱注射前15 min予腹腔给药(SCH58261 0.05 mg/kg),对照组给予同等剂量生理盐水。在成功诱导癫痫发作40 min后予地西泮及水合氯醛终止发作,并于发作终止后24 h留取标本。尼氏染色法检测三组中海马神经元损伤情况,Westernblot法检测MAPKs(JNK/p-JNK、P38/p-P38和ERK/p-ERK)表达变化。结果对照组、模型组及A2A受体阻断剂组双侧海马CA3区正常形态神经元计数分别为158.6±8.4、59.8±7.4和123.4±5.0,模型组神经元计数显著低于对照组,差异具有统计学意义(P<0.05),A2A受体阻断剂组神经元计数显著高于模型组,差异具有统计学意义(P<0.05)。Westernblot法检测显示p-JNK、p-P38和p-ERK在模型组中表达明显增多,在A2A受体阻断剂组中p-JNK和p-P38表达减少。结论氯化锂-毛果芸香碱模型中,腺苷A2A受体阻断剂可能通过抑制p-JNK他p-P38的表达对神经元损伤起到保护作用。

Objective To investigate the effect of adenosine A2A receptor antagonist on a rat model of lithium-pilocarpine status epilepticus （SE）.Methods A total of 50 WD rats were randomly divided into control group,model group,and A2A receptor antagonist group.The rats in the model group were given intraperitoneal injection of chloride lithium-pilocarpine to establish a rat model of epilepsy,those in the A2A receptor antagonist group were given intraperitoneal administration of SCH58261 at a dose of 0.05 mg/kg before chloride lithium-pilocarpine injection,and those in the control group were given normal saline at the same dose.All rats were given diazepam and chloride aldehyde to terminate seizures at 40 minutes after successful induction of seizures,and samples were collected at 24 hours after termination of seizures.Nissl staining was used to observe hippocampal neuronal damage in the three groups,and Western blot was used to measure the changes in the expression of mitogen-activated protein kinases （JNK/p-JNK,P38/p-P38,and ERK/p-ERK）.Results The number of normal neurons in the bilateral hippocampal CA3 region was 158.6 ± 8.4 in the control group,59.8 ± 7.4 in the model group,and 123.4±5.0 in the A2A receptor antagonist group;the model group had a significantly lower number than the control group （P 〈 0.05）,and the A2A receptor antagonist group had a significantly higher number than the model group （P 〈0.05）.Western blot showed that the model group had significant increases in the expression of p-JNK,p-P38,and p-ERK,while the A2A receptor antagonist group had significant reductions in the expression of p-JNK and p-P38.Conclusions In the lithium-pilocarpine model,adenosine A2A receptor antagonist has a protective effect against neuronal damage,possibly by inhibiting the expression of p-JNK and p-p38.