REGULATION OF NEURAL PLASTICITY IN MATURING VISUAL CELLS

我们研究的长期目标是确定细胞和分子 未成熟皮质细胞对视觉的独特敏感性的基础 在出生后的早期经历。 理解关键时期 猫模型的可塑性可能有助于阐明神经机制 基础性弱视 利用1-去甲肾上腺素（1- NA）直接注入到麻醉的再生障碍性视皮层中， 瘫痪的小猫，我们想探索一种新的策略， 快速改变单个细胞的视觉优势。 针对新 有证据表明突触后活动的参与 在这个问题上的依赖机制，可能的相互作用， 视皮层内的NA-B肾上腺素受体系统将 在慢性病猫身上寻找。 将进行另一项长期研究， 深入了解可能整合两种B 肾上腺素受体和毒蕈碱受体依赖性过程 皮质可塑性的调节。我们还想进行一次彻底的 对猫视皮层再生NA终末的研究， 关于中枢神经系统轴突再生的广泛神经科学问题。 我们将在麻醉和麻痹的1-NA注入皮层中进行研究， 小猫1）双眼反应变化的时间过程 在不同的时间间隔之前和期间的光学诱导斜视 感受野映射，作为总体和单细胞基础 （“在线”修饰），2）功能性细胞类型（简单、复杂和 超复合物的终止性质），层流位置的每个 记录细胞，以及它与最近眼的中心的关系 组织学上可见的优势斑块。 以类似的 在上述背景下，我们将研究 电刺激传递到蓝斑中的NA细胞。 3)通过将蝇蕈醇局部注入受脑缺血影响的皮层区域， 在普萘洛尔输注前（无时间重叠），我们将研究 “蝇蕈醇效应”的表达是否依赖于 NA-B肾上腺素受体系统的功能。 4)我们会确认， 扩展了我们的初步研究结果， 在小猫短暂的单眼眼睑缝合后， 腹膜内注射Li 2CO 3。 5)我们还将研究 在-6-羟基多巴胺灌注的 成年猫的视觉皮层使用多学科的方法。

The long-term goal of our study is to identify cellular and molecular bases for the unique sensitivity of immature cortical cells to visual experience early in postnatal life. Understanding the critical period plasticity in the cat model may help to elucidate neural mechanisms underlying amblyopia ex anopsia. Taking advantage of plasticity-enhancing effects of 1-noradrenaline (1- NA) directly infused into aplastic visual cortex of anesthetized and paralyzed kittens, we want to explore a new strategy with which we can quickly alter ocular dominance of individual cells. In response to new evidence which suggests the involvement of postsynaptic activity- dependent mechanisms in the matter, likely interactions among such the mechanisms and the NA-B adrenoreceptor system within visual cortex will be sought in chronic kittens. Another chronic study will be made to gain insight into possible target molecules which may integrate both B adrenoreceptor - and muscarinic receptor-dependent processes int eh regulation of cortical plasticity. We also want to carry out a thorough study on regenerative NA terminals in cat visual cortex, addressing a broad neuroscience question of regeneration of CNS axons. We will study in the 1-NA-infused cortex of anesthetized and paralyzed kittens 1) time courses of changes in binocularity response to optically induced squint at various time intervals before and during receptive-field mappings, as a population and on the single-cell basis ("on-line" modification), 2) functional cell types (simple, complex and hyercomplex with end-stopping properties), laminar location of every recorded cell, and its relation to the center of the nearest ocular dominance patches which are visualized histologically. In the similar context as above, we will study the plasticity-enhancing effect of electrical stimulation delivered to the NA cells in the locus coeruleus. 3) By locally infusing muscimol into a cortical area affected by a preceding (no temporal overlap) infusion with propranolol, we will study whether the expression of the "muscimol effects" is dependent on the function of the NA-B adrenoreceptor system. 4) We will confirm and extend our preliminary results that a shift in ocular dominance following brief monocular lid suture in kittens is blocked by repeated i.p. injections of Li2 CO3. 5) We will also study the presence of genuine regenerative NA terminals in the-6-hydroxydopamine-infused visual cortex of adult cats using a multidisciplinary approach.