POSTNATAL PLASTICITY AND RECOVERY FROM BRAIN DAMAGE

产后可塑性和脑损伤的恢复

• 批准号: 3408102
• 负责人: PETER R HUTTENLOCHER
• 金额: $ 8.03万
• 依托单位: UNIVERSITY OF CHICAGO
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-04-01 至 1990-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3408102
• 关键词: cerebral cortex; chronic brain damage; histochemistry /cytochemistry; neural plasticity; newborn animals; pyramidal tracts; sensorimotor system

This study will explore the plasticity of developing cerebral cortex during the postnatal period, using the pyramidal motor system of the rat as a model. The ability of sensorimotor cortex to reorganize itself after perinatal injury and possible effects of motor activity on such reorganization will be studied. Observations will be made in 4 groups of animals. The first is a group of immature (age 1-2 week) and mature (age 90 days) normal rats, reared under standard conditions. Pyramidal tract neurons in cerebral cortex will be labelled by retrograde transport of horseradish peroxidase. The tracer will be injected unilaterally into the cervical enlargement of spinal cord. The distribution and number of labelled cortical neurons will be determined. This group will serve as a control for the experimental groups. One experimental group will have restraint of one forelimb during the period of plasticity of the pyramidal motor system. Another group will have a hemispherectomy during the first postnatal week. A third experimental group will have both a neonatal hemispherectomy and unilateral limb restraint. The limb restraint will be ipsilateral to the hemispherectomy in half, contralateral in the other half. All experimental animals will be allowed to grow to maturity (age 90 days). The number and distribution of pyramidal tract neurons in cerebral cortex will then be studied after injection of wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) into the cervical enlargement of the spinal cord, both ipsilateral and contralateral to the experimental manipulations. Quantitative data will be obtained by computer-assisted methods and results in the various groups will be examined for statistically significant differences. Knowledge concerning the extent and mechanism of plasticity in postnatal cerebral cortex is of great importance for our understanding of development of cortical function, both in the normal situation and after brain injury. It is hoped that such knowledge will eventually lead to strategies for maximizing developmental potential in man, both in the normal human infant and in infants with focal brain damage. For example, a finding of increased formation of uncrossed connections related to restraint of the limb ipsilateral to motor cortex injury would suggest a possible analogous strategy for rehabilitation of infants with the hemiplegic form of cerebral palsy.

这项研究将探讨在开发脑皮质的可塑性 产后时期，使用大鼠的锥体运动系统作为A 模型。 感觉运动皮层在 围产期损伤和运动活动对此类的可能影响 将研究重组。 观察将在4组中进行 动物。 第一个是一组未成熟（1-2周）和成熟（年龄 90天）正常大鼠，在标准条件下饲养。 锥体道 脑皮质中的神经元将通过逆行运输标记 辣根过氧化物酶。 示踪剂将单方面注入 脊髓的宫颈增大。 分布和数量 将确定标记的皮质神经元。 这个小组将作为一个 实验组的控制。 一个实验组将有 在锥体可塑性期间，一个前肢的约束 电机系统。 另一组将在第一次进行半球切除术 产后周。 第三个实验组将具有新生儿 半球切除术和单侧肢体约束。 肢体约束将是 半球切除术的同侧一半，另一个对侧 一半。 所有实验动物都将被允许生长到成熟度（年龄90岁 天）。 大脑中锥体道神经元的数量和分布 然后，将在注射小麦胚芽凝集素后研究皮质 将辣根过氧化物酶（WGA-HRP）结合到颈椎 同侧和对侧的脊髓增大 实验操作。 定量数据将通过 计算机辅助的方法和各组中的结果将是 检查是否有统计学上的显着差异。 关于产后可塑性的程度和机制的知识 大脑皮层对于我们对发展的理解非常重要 在正常情况下和脑损伤后的皮质功能。 希望这样的知识最终会导致策略 在正常的人类婴儿中，人类的发育潜力最大化 以及局灶性脑损伤的婴儿。 例如，发现 与约束有关的无交连接的形成增加 肢体对运动皮层损伤的肢体损伤可能表明可能类似 用大脑偏瘫形式恢复婴儿的策略 麻痹。