MATURATION OF RESPIRATORY NEURAL SITES: RELATION TO SIDS

该研究计划将使用最新技术来评估神经系统 活动，即内在光学成像，连同单个神经元 表面记录。 这项研究计划将研究喙部大脑 影响发育动物睡眠期间呼吸控制的区域 这样就可以了解受害者呼吸衰竭的机制 的SIDS。 状态影响改变嘴侧脑下行输入 区域到特定的脑干呼吸区，并将发育中的 通过差异性增强，生物体面临阻塞性睡眠呼吸暂停的风险 在上呼吸道上的呼吸作用。吻部影响的程度 随着发展而变化。 在吻侧脑区中， 下丘脑/视前区的呼吸受到实质性影响， 介导对呼吸部位的热影响。 睡眠状态可以 减少或消除下降的热驱动，从而钝化一个大的 唤醒介导的上气道肌肉激活的组成部分。 我们将 检查下丘脑前部神经活动的发展， 通过1）检查小猫在3个年龄段的呼吸模式 视前区/下丘脑前部的“自发”神经活动， 在雨夹雪和清醒时， 并将该活动与上呼吸道和呼吸道模式相关联， 以及2）通过以下方式在视前区/下丘脑前部区域中唤起活动： 吻侧脑部位的环境和局部变暖，并检查 对局部和脑干神经相互作用的影响， 将用固有光学成像评估总体活性 程序. 呼吸依赖性将通过交叉- 将电池放电与隔膜和鞋面的图案化相关联 气道扩张器（环杓后肌）;回归手术将 确定与呼吸周期的各个方面以及与 血压. 诱发的活动包括视前区的升温 区域，以操纵温度“驱动”呼吸， 睡眠-觉醒状态，分级低氧和高碳酸血症 挑战和药理学升压刺激。

The research program will use the latest technology for assessing neural activity, that of intrinsic optical imaging, together with single neuron and surface recording. The research plan will examine how rostral brain areas affect respiratory control during sleep in the development animal so that mechanisms of respiratory failure can be understood in victims of SIDS. State influences modify descending input from rostral brain regions to specific brainstem respiratory areas, and place the developing organism at risk for obstructive sleep apnea by differentially enhancing diaphragmatic over upper airway action.; the extent of rostral influences vary with development. Among rostral brain areas, the anterior hypothalamus/preoptic area exters substantial breathing influence by mediating thermal influences to respiratory sites. Sleep states can diminish or abolish descending thermal drive, thus blunting a large component of arousal-mediated upper airway muscle activation. We will examine the development of anterior hypothalamic neural activity to respiratory patterns at 3 ages in the kitten by 1) examining "spontaneous" neural activity in the preoptic/anterior hypothalamus and in the motor column of branchial arch muscles during sleet and waking, and relating this activity to upper airway and diaphragmatic pattering, and 2) evoking activity in preoptic/anterior hypothalamic regions by environmental and local warming of the rostral brain site, and examining the resultant influences on local and brain stem neural interactions and overall activity will be assessed with intrinsic optical imaging procedures. Respiratory dependencies will be determined by cross- correlating cell discharge with patterning of the diaphragm and an upper airway dilator (the posterior cricoarytenoid); regression procedures will determine relationships with aspects of the respiratory cycle and with blood pressure. Evoked activity will include warming of the preoptic region to manipulate temperature "drive" to respiration during each sleep-waking state, graded hypoxic and hypercapnic ventilatory challenges, and pharmacologic pressor stimulation.