腺苷A1受体敲除小鼠在戊四氮点燃过程中的癫癇病间发作情况和脑组织病理形态学变化

The role of adenosine A1 receptors in seizures and histomorphology changes in mice after pentylenetetrazol-kindled epilepsy

目的:探讨腺苷A1受体与癫癇病间发作及神经保护的关系。方法:将实验小鼠分为敲除鼠组(腺苷A1受体基因敲除小鼠,20只)、野生型组(C57BL/6型普通小鼠,20只)和对照组(未接受PTZ点燃的野生型小鼠,10只),采用PCR法对实验小鼠进行基因鉴定并据此分组,观察3组小鼠在PTZ点燃过程中的癫癇病间发作情况(病死率、点燃率、点燃潜伏时间、发作开始时间、发作持续时间、癫癇病间发作级别的数量等),并在PTZ点燃后2个时间点(24 h,30 d)处死小鼠,对其冰冻切片进行HE染色观察皮层和海马的形态结构。结果:敲除鼠组病死率和点燃率均显著高于野生型组(均P<0.05);敲除鼠组点燃潜伏时间、发作开始时间明显短于野生型组,发作持续时间明显长于野生型组(均P<0.05);敲除鼠组癫癇病间发作程度明显重于野生型组。点燃后不同时间点动物脑组织病理形态学结果显示敲除鼠组损伤较野生型组出现更早、范围更广泛、损伤程度更重。主要表现为早期反应性小胶质细胞增生、细胞肿胀,晚期神经细胞变性、坏死、异常增多的畸形胶质细胞。结论:腺苷A1受体敲除鼠具有特殊的癫癇病间易感性,腺苷A1受体具有极强的脑保护作用,可减轻PTZ点燃过程中的脑组织形态结构损伤。

Objective： To explore the relationship between adenosine A1 receptors and seizures of epilepsy as well as neuroprotection. Methods： The experimental animals were divided into wild type （WT） group （n =20）, adenosine A1 receptors knock-out （KO） group（n = 20） , and control group （n = 10）. The mortality, kindling rate, mean times to onsets, start times of seizures, durations of seizures, and the behavioral seizure scales of mice subjected to the pentylenetetrazol （PTZ） -induced kindling of seizures in two groups were measured and compared. HE staining was adopted to observe the histomorphology of cortex and hippocampus of mice in two groups at 24 hours and 30 days post-kindling. Results ： The mortality and kindling rate in KO group were significantly higher than those in WT group （ P 〈 0.05 ）. The mean times to onsets and start times of seizures in KO group were significantly shorter than those in WT group, while the durations of seizures in KO group were significantly longer than that in WT group （ P 〈 0.05 ）. Mice in KO group showed a significant increase in behav- ioral seizure stage scores compared with those in WT group （P 〈 0.05 ）. Mice in KO group showed a more serious damage in brain tissues （reactivity of microglia, neuronal necrosis, astrocytosis, ere） than those in WT group. Conclusions： Adenosine A1 receptors knock-out mice have more susceptibility to seizures. Adenosine A1 receptors may play a neuroprotective role in seizures.