DISCHARGE PATTERNS OF MOTONEURONS

描述(由申请人提供)：我们研究的总体目标是 一直了解脊椎的机制和功能组织 突触前控制突触效应的通路 肌肉、皮肤和关节传入及其在运动中的作用 表演和感官辨别。第一，也许是最吸引人的问题 这是我们在过去几年中进行的研究得出的结论， 是发现了产生不同抑制作用的中枢机制 脊髓内初级传入去极化(PAD) 个体肌梭传入的侧枝。这使得，至少在 原理，对外围产生的信息进行选择性寻址 特定的神经元组。这项提议的具体目的之一是 分析在肌肉中观察到的PAD差异控制的程度 而皮肤传入对突触后的任何功能影响 这些输入在不同的靶神经元集合中引发的反应。 突触前控制机制的另一个相对未被研究的方面是 它对炎症和外周反应的可塑性和适应性 神经损伤或传导阻滞。我们现在建议研究一下，在麻醉状态下 CAT在突触前控制关节突触活动中的变化 在急性关节和皮肤炎症期间的传入，鉴于明显的 炎症过程引起的反射行为的变化，以及 皮肤传入信息传递的突触前控制的变化 在周围神经损伤或导致的脊髓反射被揭发后 传导阻滞。我们最近已经证明，在被麻醉的猫体内， 一组自发活动的调节冲动的背角神经元 在几条脊髓通路中的传递，包括那些介导突触前的通路 肌肉和皮肤传入的抑制。我们现在将探索 这组神经元和一些通路的功能组织和 可能涉及其活动同步的机制，以及 周围神经损伤和急性炎症是如何改变这种活动的 皮肤上的。

DESCRIPTION (provided by applicant): The general objective of our research has been to understand the mechanisms and functional organization of the spinal pathways involved in the presynaptic control of the synaptic effectiveness of muscle, cutaneous and joint afferents and the role of these mechanisms in motor performance and sensory discrimination. One, perhaps the most attractive issue that has emerged from the studies we have performed during the last few years, is the finding of central mechanisms that produce a differential inhibition of the primary afferent depolarization (PAD) elicited in the intraspinal collaterals of individual muscle spindle afferents. This allows, at least in principle, a selective addressing of the information generated in the periphery to specific sets of neurons. One of the Specific Aims of this proposal is to analyze the extent to which the differential control of PAD observed in muscle and cutaneous afferents has any functional consequences on the postsynaptic responses elicited by these inputs in different sets of target neurons. Another, relatively unexplored aspect of the presynaptic control mechanisms, is its plasticity and adaptability in response to inflammation and peripheral nerve damage or conduction block. We now propose to study, in the anesthetized cat, the alterations in the presynaptic control of synaptic actions of joint afferents during acute inflammation of joints and skin, in view of pronounced changes in reflex actions caused by inflammatory processes, as well as the changes in the presynaptic control of transmission from cutaneous afferents following the unmasking of spinal reflexes caused by peripheral nerve damage or conduction block. We have shown recently that in the anesthetized cat there is a set spontaneously active dorsal horn neurons that modulates impulse transmission in several spinal pathways, including those mediating presynaptic inhibition of muscle and cutaneous afferents. We will now explore the functional organization of this set of neurons and some of the pathways and mechanisms that may be involved in the synchronization of their activity, and how this activity is modified by peripheral nerve damage and acute inflammation of the skin.