MONOAMINERGIC CONTROL OF DEVELOPING VISUAL NEURONS

这项研究的总体目标是建立视觉之间的联系 出生后关键期和中枢的皮质可塑性 含有儿茶酚胺的系统。作为我们先前发现的延伸 在本主题中，我们将进一步探索恢复大脑皮质的方法 大脑的可塑性，失去可塑性的原因是 儿茶酚胺能神经末梢特异性耗竭或单纯 已过了敏感期。为了刺激 β-肾上腺素受体，或更直接地，腺苷环化酶，各种化学物质 药剂将通过一种 长期植入的微灌流系统。在寻找一种非侵入性 中枢去甲肾上腺素-β-肾上腺素受体-环磷酸腺苷的激活途径 系统，我们将在电气和化学上刺激 脑干内含去甲肾上腺素的胞体 蓝斑，视皮层完好无损。作为一家久负盛名的 视皮层感受野神经元可塑性的测定 单个视觉皮质细胞的特性，特别是双眼性 将在小猫和成年猫的单眼遮挡后进行检查。 这些动物将同时受到各种操纵 如上所述的中枢儿茶酚胺系统。除了……之外 这些主要是生理学研究，正是为了 加强中枢儿茶酚胺系统与视觉的联系 大脑皮层的可塑性，我们也想研究这一看似合理的联系 全球范围更广。然后我们将研究，在形态上以及 在生化方面，内源性儿茶酚胺和 在猫视皮质中的相关受体，以比较 视皮层细胞成熟的中枢儿茶酚胺系统 以及他们对异常视觉体验的敏感性。

The general goal of this study is to establish the link between visual cortical plasticity during the postnatal critical period and the central catecholamine-containing system. As an extension of our previous findings in this topic, we will further explore means of restoring cortical plasticity in the brain which haf lost plasticity either due to the specific depletion of catecholaminergic nerve terminals or simply outgrowing the susceptible period. In order to stimulate Beta-adrenoreceptors or, more directly, adenylate cyclase, various chemical agents will be delivered continuously into the visual cortex through a chronically implanted microperfusion system. In search for a noninvasive way to activate the central norepinephrine-Beta-adrenoreceptors-cyclic AMP system, we will stimulate, electrically and chemically, the norepinephrine-containing cell bodies in the brainstem at the locus coeruleus, leaving the visual cortex totally intact. As a well-established assay for neuronal plasticity in the visual cortex, receptive field properties, binocularity in particular, of single visual cortical cells will be examined following monocular occlusion in kittens and adult cats. These animals will be concurrently subjected to a variety of manipulations of the central catecholamine system as mentioned above. In addition to these primarily physiological studies which are precisely designed to tighten up the link between the central catecholamine system and visual cortical plasticity, we want also to study this plausible link in a much more global scope. We will then study, morphologically as well as biochemically, the postnatal maturation of endogenous catecholamines and related receptors in the cat visual cortex so as to compare ontogeny in the central catecholamine system with the maturation of visual cortical cells and their susceptibility to abnormal visual experience.