FUNCTIONAL RECOVERY FOLLOWING NEURAL INJURY IN EMBRYOS

对于基础和临床神经科学来说，一个重要的问题是为什么 发育中的神经系统似乎更有能力进行功能修复 比成年人受伤更严重。一个相关的问题是，成年神经元是否可以 受伤后恢复使用-开发中成功使用的机制 神经元。尽管在这一领域进行了密集的研究，但很少有研究分析 发育中单个神经元与成年神经元的反应 动物在解剖、生理和行为方面的恢复 受伤后的功能障碍。在水蛭里比较单纯的紧张 系统不仅可以研究行为，它的调制和 潜在的神经元回路，也是离散病变对 个人关系和行为。此外，许多神经元是 在胚胎发育的早期就可以识别，从而可以研究 正常和正常个体神经元及其连接的发育 受伤的胚胎。这一建议集中在大脑中的单个中间神经元上。 水蚤，S细胞，在成年动物中，它通过 独特的时尚。此外，S细胞已经被证明是 感觉-运动反射的正常非联想学习所必需的 (缩写)尽管它不是反身行为所必需的，但 只是为了它的修改。杀死S细胞的胚胎损伤导致 形成至少一个可恢复正常的异常连接 生理功能。本提案测试中概述的实验 关于胚胎使用的细胞机制的特定假说 神经元形成非典型连接以及这些连接的能力 支持非联想学习。此外，非典型系统的稳定性 在发育过程中形成的联系可以在成年后进行分析。 实验方法包括解剖学、生理学和行为学。 S细胞突触连接的联合表征技术， 损伤后形成的非典型连接及其与 非联想学习。这些实验将提供对 神经系统发育过程中的细胞机制 胚胎和成体对损伤的代偿反应及其机制 用于复杂行为的恢复。

A question important to basic and clinical neuroscience is why the developing nervous system seems more capable of functional repair after injury than the adult. A related question is whether adult neurons can recover from injury using-mechanisms successfully employed by developing neurons. Despite intense research in this area, few studies have analyzed the response of single identified neurons in developing versus adult animals with regard to anatomical, physiological and behavioral recovery of function following injury. In the leech's relatively simple nervous system it is possible to study not only behavior, its modulation and the underlying neuronal circuit, but also the effects of discrete lesions on individual connections and behavior. In addition, many neurons are identifiable early in embryogenesis, allowing investigations into the development of individual.neurons and their connections both in normal and injured embryos. This proposal is focussed on a single interneuron in the leech, the S cell, which in adult animals responds to injury in a characteristic fashion. In addition, the S cell has been shown to be essential to normal nonassociative learning of a sensory-motor reflex (shortening) even though it is not required for the reflexive behavior but only for its modification. Embryonic lesions that kill an S cell cause the formation of at least one aberrant connections that restores some normal physiological functioning. Experiments outlined in this proposal test specific hypothesis concerning the cellular mechanisms used by embryonic neurons to form atypical connections and the ability of these connections to support nonassociative learning. In addition, the stability of atypical connections formed during development can be analyzed later in adulthood. Experimental methods include anatomical, physiological and behavioral techniques in combination to characterize S cell synaptic connections, atypical connections formed following injury and their link to nonassociative learning. These experiments will provide insights into cellular mechanisms underlying the developing nervous system's compensatory response to injury and into mechanisms in embryos and adults for the recovery of complex behavior.