CAJ | 학술논문

目的探讨颅内不同起源的肌阵挛与脑损伤的关系及其病理学特征.方法选择GABAA受体拮抗剂SR95531在成年SD大鼠的初级运动皮层(PMC)、纹状体(CS)、丘脑网状核(NRT)以及L-5-HTP在幼年豚鼠桥脑背侧微量注射,建立皮层-丘脑轴起源和脑干起源的肌阵挛动物模型.分别在发作达峰后10 min、30 min对各组行股动脉取血以检测血清特异性神经元烯醇化酶(NSE),并留取诱导剂注射部位对侧额叶皮层及海马行HE染色及Nissl染色,TUNEL法检测细胞凋亡,免疫组化染色检测Bcl-2、Bax蛋白表达.结果 (1)PMC组、CS组和NRT组在发作达峰后30 min时血清NSE水平较对照组明显增高,差异有统计学意义(P＜0.05),其中以PMC组最明显.(2)HE染色见PMC组、CS组和NRT组额叶皮层及海马CA3区神经细胞明显变性及坏死,而桥脑背侧组未出现明显的病理学改变.Nissl染色见PMC组、CS组和NRT组额叶皮层神经细胞计数较对照组减少56.3%～66%,而桥脑背侧组无明显异常.(3)PMC组、CS组和NRT组额叶皮层和海马CA3区凋亡阳性细胞计数较对照组升高20.4～40.7倍,而桥脑背侧组凋亡阳性细胞计数无明显增加.(4)PMC组、CS组和NRT组额叶皮层和海马CA3区Bax蛋白表达均较对照组明显增高,Bcl-2蛋白表达明显降低,差异有统计学意义(P＜0.05),而桥脑背侧组与对照组比较差异无统计学意义.结论 PMC、CS和NRT等皮层-丘脑轴起源的肌阵挛发作可引起额叶皮层、海马神经细胞明显减少等组织学损伤,其损伤的发生与肌阵挛痫性放电激活神经细胞凋亡和坏死过程相关,因而属于惊厥性脑损伤.脑干起源的肌阵挛未见明显异常.
목적 탐토로내불동기원적기진련여뇌손상적관계급기병이학특정.방법 선택GABAA수체길항제SR95531재성년SD대서적초급운동피층(PMC)、문상체(CS)、구뇌망상핵(NRT)이급L-5-HTP재유년돈서교뇌배측미량주사,건립피층-구뇌축기원화뇌간기원적기진련동물모형.분별재발작체봉후10 min、30 min대각조행고동맥취혈이검측혈청특이성신경원희순화매(NSE),병류취유도제주사부위대측액협피층급해마행HE염색급Nissl염색,TUNEL법검측세포조망,면역조화염색검측Bcl-2、Bax단백표체.결과 (1)PMC조、CS조화NRT조재발작체봉후30 min시혈청NSE수평교대조조명현증고,차이유통계학의의(P＜0.05),기중이PMC조최명현.(2)HE염색견PMC조、CS조화NRT조액협피층급해마CA3구신경세포명현변성급배사,이교뇌배측조미출현명현적병이학개변.Nissl염색견PMC조、CS조화NRT조액협피층신경세포계수교대조조감소56.3%～66%,이교뇌배측조무명현이상.(3)PMC조、CS조화NRT조액협피층화해마CA3구조망양성세포계수교대조조승고20.4～40.7배,이교뇌배측조조망양성세포계수무명현증가.(4)PMC조、CS조화NRT조액협피층화해마CA3구Bax단백표체균교대조조명현증고,Bcl-2단백표체명현강저,차이유통계학의의(P＜0.05),이교뇌배측조여대조조비교차이무통계학의의.결론 PMC、CS화NRT등피층-구뇌축기원적기진련발작가인기액협피층、해마신경세포명현감소등조직학손상,기손상적발생여기진련간성방전격활신경세포조망화배사과정상관,인이속우량궐성뇌손상.뇌간기원적기진련미견명현이상.
Objective To explore the possibility of brain damage caused by myoclonic seizures of different origins and its pathologic characteristics. Methods Fifty-six adult SD rats were randomly divided into pontine micturition center (PMC) microinjection group (n=16), corpus striatum (CS) microinjection group (n=16), reticular thalamic nucleus (RTN) microinjection group (n=16), and normal control group (n=8);24 infant Guinea Pigs were randomized into dorsal pons microinjection group (n=16) and normal control group (n=8);Models of myoclonic seizures of different origins were established by microinjecting SR95531 into the PMC, CS and NRT of adult SD rats, and microinjecting L-5-HTP into the dorsal pons of Guinea Pigs, respectively. Blood from femoral artery was drawn 10 and 30 minutes after the peak time of myoclonic seizures from PMC, CS and NRT areas of rats and from dorsal pons of Guinea Pigs to detect the level of neuron-specific enolase (NSE). All animals were sacrificed 10 and 30 minutes after the peak time of myoclonic seizures and the contralateral brain at the microinjecting sites were isolated for following study: morphology in the frontal cortex and the CA3 region of hippocampus was observed by HE staining and Nissl staining;apoptosis cells in the frontal cortex and the CA3 region of hippocampus were detected by TUNEL;protein expressions of apoptosis-related Bcl-2 and Bax were detected by immunohistochemistry. Results Significant neurodegeneration and neuronal necrosis were found by HE staining in the frontal cortex and the CA3 region of hippocampus of the myoclonus originating from PMC, CS and NRT;however, no obvious histopathologic changes were observed in the cortex of Guinea Pigs with myoclonus arising from the dorsal pons. Cell count at the frontal cortex by Nissl staining was less by 56.3%-66% (30 minutes of peak time) than that in the normal control group;however, no obvious loss of cell was observed in the cortex of the Guinea pigs with myoclonus originating from dorsal pons. The serum level of NSE was increased in all rats with myoclonus originating from PMC, CS and NRT, especially in those from PMC. TUNEL-positive cells in the frontal cortex and hippocampus caused by myoclonic seizures originating from PMC, CS and NRT were increased by 20.4-40.7 times remarkably as compared with those in the controls, but no significant increase of apoptosis cells in the Guinea pigs with myoclonus originating from dorsal pons was noted. As compared with those in the controls, significant increase of Bax protein expression and obvious decrease of Bcl-2 protein expression in the frontal cortex and hippocampus of those animals with myoclonus arising from PMC, CS and NRT were found (P<0.05);no obvious differences in those of the animals with myoclonus arising from dorsal pons were noted as compared with those of its control group (P>0.05).Conclusion The myoclonus seizure arising from the axis of cortical-thalamus but not the dorsal pons can induce the decrease of neurocytes in the susceptive area of cortex and CA3 region. The brain damage in the cortex with the myoclonic seizures originating from the axis of cortical-thalamus is caused by the epileptic discharges of myoclonus which activates the process of necrosis and apoptosis of the neurocytes in brain, which belongs to the brain injury induced by seizures. However, there is no obvious damage in cortex of the models with the myoclonus originating from the dorsal pons of Guinea Pigs.