波谱学杂志 ›› 2001, Vol. 18 ›› Issue (3): 193-200.

• 研究论文 •    下一篇

慢性电刺激海马结构诱发大鼠脑磁共振成像异常信号分析

臧颖1,韩丹1*,杨运煌2,刘买利2,邹祖玉3,曾俊3   

  1. 1.武汉大学医学院 生理学教研室,武汉 430071;2.中国科学院武汉物理与数学研究所 波谱与原子分子物理国家重点实验室,武 汉 430071;3.武汉大学医学院 病理学教研室,武汉 430071
  • 收稿日期:2001-04-17 修回日期:2001-06-06 出版日期:2001-09-05 发布日期:2001-09-05
  • 作者简介:臧颖(1974-),女,硕士研究生.*通讯联系人
  • 基金资助:

    波谱与原子分子物理国家重点实验室开放基金资助项目(N o:99T1509) 和湖北省自然科学基金资助项目(No:29925515).

ABNORMAL T2-WI SIGNAL IN CHRONIC EPILEPTIC RATS INDUCED BY DELIVERING REPETITIVE TETANUS INTO THE APICAL DENDRITE REGION IN
EITHER CA1 OR DENTATE GYRUS

ZANG Ying1, HAN Dan1*, YANG Yun-huang2, LIU Mai-li2, ZHOU Zu-yu3, ZENG Jun3   

  1. 1.Department of Physiology, Medical College, Wuhan University, Wuhan 430071; 2.State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, The Chinese Academy of Science, Wuhan 430071; 3.Department of Pathology, Medical College, Wuhan University, Wuhan 430071
  • Received:2001-04-17 Revised:2001-06-06 Online:2001-09-05 Published:2001-09-05
  • About author:*Correspondence author
  • Supported by:

    波谱与原子分子物理国家重点实验室开放基金资助项目(N o:99T1509) 和湖北省自然科学基金资助项目(No:29925515).

摘要:

为探讨海马结构(hippocampal formation)功能失衡与癫痫源性脑损伤的关系,本工作采用 慢性强直电刺激大鼠海马(hippocampus, HPC) CA1顶树突区(apical dendrite region, A DR)或齿状回(dentate gyrus, DG)诱发大鼠癫痫模型,一天一次,连续刺激6~8天后, 观察人工致痫灶以外的横向弛豫时间加权的核磁共振(T2 weighted magnetic reson ance im age, T2-WI) 绝对信号值变化(片厚1mm),以及深部电图和原发性湿狗颤抖(pri mary wet dog shakes, WEDS),并对被检测动物T2-WI信号异常的相应脑区进行组织学鉴定. 结果表明:(1)电 刺激大 鼠ADR或DG的作用基本相似,引起深部电图的癫痫样电活动和侧脑室区域T2值增强. (2)含有电极尖端痕迹的核磁共振(magnetic resonance image,MRI)脑切片出现对称性腹部侧脑室区域T2值增强,连续向后1mm取MRI脑切片进行观察发现,对侧腹部侧脑室区域信号异常. (3)组织学切片观察到:MRI检测的侧脑室区域T2-WI信号增强与组织切片的侧脑室扩大相吻合,可见扩大的侧脑室中脉络丛上皮细胞病理性增生现象. 提示:在大鼠癫痫点燃现象出现之前,过度激活DG或ADR均可引起相似的早期癫痫源性脑损伤.

关键词: 顶树突区§齿状回, MRI, 癫痫, 大鼠

Abstract:

The chronic rat temporal epilepsy was induced by repetitive tetanus (60Hz, 0.4~0.6mA , 2s) to the apical dendrite region (ADR) in either CA1 or the dentate gyrus ( DG ) once a day for 6 or 8 days. T2-weighted MRI (T2-WI) measurements  and morpholog ical observations were performed on the tetanized rats. A resemble increase of MRI signal intensity in the lateral ventricle area was observed both in the ADR- tetanized rats and the DG-tetanized rats. There is an asymmetric T2-WI ab normaliti es in the anterior MRI slices and ventral T2-WI abnormalities contralater al to t he implantation side in the posterior MRI slices (1 mm posterior to the anterior  MRI slice). Morphological identification showed that there are the enlarged lat e ral ventricle and pathological ventricular chorodea plexus hyperplasia which cor respond to the MRI observations. The results suggested that the activation of DG or  ADR in an intrinsic hippocampal circuit may play the same role in epileptogenesis.

Key words: Apical dendrite, Dentate gyrus, MRI, Epilepsy, Rats

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