Association Fiber Induced Plasticity In Olfactory Cortex

描述(由申请人提供)：拟议研究的目标是 加深对嗅觉加工及其在嗅觉中的作用的了解 嗅皮层联合纤维系统的可塑性。高频 刺激嗅皮层联合纤维先前已被证明 在诱发场电位中诱导一种新形式的增强。建议数 研究将使用以下方法来研究这种增强的潜在事件 完好动物嗅皮层神经元的细胞内记录， 这使得在研究细胞内效应的同时保留了网络 大脑皮层的特性。初步数据显示，主要的 高频联合纤维刺激产生的细胞内效应， 每天重复4至6天，是明显的超极化 嗅皮层锥体细胞的膜电位。拟议的研究 将进一步表征这种细胞内的反应，并探索其功能 意义。拟议研究的具体目的是：1)比较 高频联合纤维刺激幼虫的细胞内效应 与先前增强的动物进行比较，以确定先前的增强是否 产生这种效果所必需的；2)确定细胞内是否 超极化是通过加强抑制或减少突触来实现的 驱动(脱臼)；以及3)检查增强对 嗅皮层锥体细胞对传入神经刺激的反应 通向皮质(侧嗅束)的通路，用两种电信号测试 刺激和自然产生的气味。这项研究将提供一种 对理解嗅觉加工有重要贡献，因此有助于 对嗅觉障碍的理解和最终的治疗。

DESCRIPTION (provided by applicant): The goal of the proposed research is to increase understanding of olfactory processing and the role played in olfactory plasticity by the olfactory cortex association fiber system. High-frequency stimulation of olfactory cortex association fibers has previously been shown to induce a novel form of potentiation in evoked field potentials. The proposed research will investigate the events underlying this potentiation using intracellular recordings from neurons in the olfactory cortex of intact animals, which permits the study of intracellular effects while preserving the network properties of the cortex. Preliminary data indicate that the primary intracellular effect produced by high-frequency association fiber stimulation, repeated daily for 4 to 6 days, is a pronounced hyperpolarization of the membrane potential of olfactory cortex pyramidal cells. The proposed research will further characterize this intracellular response and explore its functional significance. Specific aims of the proposed research are to: 1) compare the intracellular effects of high-frequency association fiber stimulation in naive vs. previously potentiated animals to determine whether prior potentiation is necessary to produce this effect; 2) determine whether the intracellular hyperpolarization is accomplished by enhanced inhibition or reduced synaptic drive (disfaciliation); and 3) examine the effect of the potentiation on the response of olfactory cortex pyramidal cells to stimulation of the afferent pathway to the cortex (lateral olfactory tract), tested with both electrical stimulation and naturally occurring odors. This research will provide an important contribution to the understanding of olfactory processing, thus aiding in the understanding and eventual treatment of olfactory disorders.