IMAGING EPILEPTIFORM EVENTS IN JUVENILE NEOCORTEX

描述：（来自申请人的摘要）癫痫影响约2%的 世界人口中，尤其是儿童。相对 关于癫痫发作如何传播和招募， 显然是正常的皮层回路考虑到大脑皮层的复杂性， 其中有几十类兴奋性和抑制性神经元参与了 不同的电路功能，很可能是启动和传播的 癫痫放电是由特定的神经元控制的 班在过去的十年里，我们开发了一种光学方法， 从神经元群体中进行钙成像，以研究新皮层回路， 用双光子激发三维成像它们的激活。使用 这种策略，我们可以光学检测细胞体中的动作电位， 几十个或几百个神经元，用单个细胞成像癫痫样事件 分辨和检测哪些神经元参与不同类型的 癫痫样事件我们提出了一个系统的努力，以了解的作用， 不同类别的新皮层神经元在启动和传播的 癫痫我们将使用神经元群体的钙成像， 药物诱导的青少年大脑皮层脑片癫痫样事件 (P9- P20）大鼠躯体感觉皮层，以便更好地了解电路 负责青少年癫痫的机制，并在同一时间图像 从发作间期到发作事件的转变。实验将在 结合全细胞记录和生物胞素重建， 最先进的成像技术，包括双光子显微镜， 光电二极管阵列和快速冷却CCD相机。我们的首要目标是 从形态学和生理学上表征参与 自发和诱发的发作间期和发作癫痫样事件。我们的最终目标 是应用一种新的光学探测方法来重建电路 通过揭示突触后靶点， 由第51 B层神经元或其他潜在的关键细胞类别触发。 这些问题的答案可能具有治疗意义， 靶向特定的神经元或细胞层， 癫痫样事件此外，我们的研究结果将特别有用， 确定负责降低的细胞和电路机制 发育期和幼年期新皮层的癫痫发作阈值以及从 发作间期至发作事件。

DESCRIPTION: (from applicant's abstract) Epilepsy affects about 2 percent of the world population and is particularly frequent in children. Relatively little is known about how epileptic seizures propagate across and recruit apparently normal cortical circuits. Given the complexity of the neocortex, where dozens of classes of excitatory and inhibitory neurons are involved in different circuit functions, it is likely that the initiation and spread of epileptic discharges are differentially controlled by specific neuronal classes. Over the last decade, we have developed an optical approach using calcium imaging from population of neurons to study neocortical circuits and to image their activation in three dimensions with 2 photon excitations. Using this strategy, we can optically detect action potentials in the somata from dozens or hundreds of neurons, image epileptiform events with single cell resolution and detect which neurons participate in different types of epileptiform events. We propose a systematic effort to understand the role of different classes of neocortical neurons in the initiation and propagation of epilepsy. We will use calcium imaging of neuronal populations during pharmacological-induced epileptiform events in neocortical slices from juvenile (P9 - P20) rat somatosensory cortex, in order to better understand the circuit mechanisms responsible for juvenile epilepsy and at the same time image the transition from interictal to ictal events. The experiments will be carried out combining whole cell recordings and biocytin reconstructions with state-of-the-art imaging techniques, including two-photon microscopy, a photodiode array and a fast cooled CCD camera. Our first goal is to characterize morphologically and physiologically the neurons involved in spontaneous and evoked interictal and ictal epileptiform events. Our final goal is to apply a novel optical probing method to reconstruct the circuitry underlying epileptiform events by revealing the postsynaptic targets that are triggered by layer 5 IB neurons, or other potentially key cell classes. The answers to these questions could have therapeutic implications for targeting specific neurons or cell layers which play a critical role in epileptiform events. Also, our results will be particularly useful in identifying the cellular and circuit mechanism responsible for the lower seizure threshold of developing and juvenile neocortex and the transition from interictal to ictal events.