3日龄未成熟大鼠缺血性脑损伤后神经行为发育及运动变化

摘要

目的 探讨3日龄未成熟大鼠缺血性脑损伤后脑组织病理表现、生理发育、神经行为和运动发育情况.方法 选取3日龄雄性SD新生大鼠96只,随机分为对照组和实验组.对照组仅切开颈部皮肤;实验组结扎双侧颈总动脉.记录两组大鼠从术后1 d起至生后3周体重,对比其生理发育情况,并对眼睑反射、竖耳、门齿萌出等感觉反射进行评估,对其四肢放置、抓握反射、翻正反射、负向趋地性等运动反射进行评价.取两组大鼠术后24 h及生后3周脑组织,行苏木精-伊红(HE)染色及免疫组织化学染色,观察脑组织病理改变.结果 术后实验组大鼠较对照组体重增加缓慢、睁眼及惊跳反射延迟、下肢放置及抓握反射抑制、负向趋地性运动能力下降(P均<0.05).实验组大鼠HE染色显示早期皮质下、脑室周围白质疏松,后期胶质细胞增生、脑室扩大、白质软化灶形成;免疫组织化学染色出现髓鞘发育障碍.结论 3日龄未成熟大鼠缺血性脑损伤后可造成脑白质损伤,出现生长发育迟缓及神经运动发育障碍等表现.%Object To investigate the pathological changes,physiological condition,neurobehavior and motor development of the 3-day-old rats with ischemic brain injury.Methods Ninety six 3-day-old male Sprague-Dawley rats were randomly assigned to experimental and control groups.Occlusion of both carotid arteries was performed in the experimental group,while the rats in the control group only received skin incisions without carotid ligation.Physical examinations and neurobehavioral development of the rats were recorded daily from the first day after operation until 3 weeks after birth,including weight,eye opening, incisor eruption,ear unfolding,righting reflex,negative geotaxis,limb placing and grasping reflex. Specimens of the brain tissue were obtained in 24 hours after operation and 3 weeks after birth for the hematoxylin-eosin staining and immunohistochemistry staining to investigate the pathological changes.All the reaults were compared between the 2 groups.Results Compared with the control group,rats in the experimental group were found growth retardation,suppression of primitive reflexes and impaired motor abilities (P < 0.05 ).The brain tissue obtained from the rats after operation showed white matter rarefaction,liquefaction and microglia hyperplasia with Hematoxylin-eosin staining and myelin formation disorder with immunohistochemistry staining.Conclusions Ischemic brain injury of the 3-day-old rats could result the mental retardation,neurobehavioral and motor development disorder because of the white matter injury.