CARDIOPULMONARY/SOMATIC INPUT TO MEDULLARY ON/OFF CELLS

最近的研究表明，可能的痛觉调制神经元(ON) 和外周细胞)接受体外循环。 输入和可能调节动脉血压以及伤害性感觉。 因此，本提案的总体目标是履行 定量描述其作用的电生理学研究 ON和OFF细胞在脊髓伤害性感觉和动脉调节中的作用 血压。这将通过确定以下程度来实现 心肺和躯体输入到这些神经元的会聚和通过 神经活动变化与动脉血变化的关系 压力和伤害感。躯体刺激将包括无害的触摸， 有毒的夹杂物和有害的辐射热。心肺刺激会 包括电刺激颈部迷走神经传入， 迷走神经传入的药物激活，静脉注射 苯肾上腺素引起的动脉血压升高，以及 静脉注射硝普钠可降低动脉血压。 将在两只完好的大鼠身上进行心肺刺激测试 以及心肺去传入的大鼠。 这项建议的具体目标是：(1)量化 描述迷走神经或高压压力感受器的影响 动脉血压控制中的ON和OFF细胞传入 伤害性甩尾反射的调制，(2) 定量确定轨迹的贡献 蓝斑/蓝下核和延髓旋转腹外侧区至迷走神经- 脊髓顶叶调控中ON和OFF细胞的介导变化 伤害性感觉、动脉血压调节和内脏-内脏 以及内脏-躯体会聚。

Recent investigations suggest that putative pain modulatory neurons (ON and OFF cells) in the rostroventral medulla receive cardiopulmonary input and may regulate arterial blood pressure as well as nociception. The overall objective of the present proposal, therefore, is to perform electrophysiological studies that quantitatively characterize the role of ON and OFF cells in the regulation of spinal nociception and arterial blood pressure. This will be accomplished by determining the degree of convergence of cardiopulmonary and somatic input to these neurons and by relating changes in neural activity to changes in arterial blood pressure and nociception. Somatic stimuli will include innocuous touch, noxious pinch, and noxious radiant heat. Cardiopulmonary stimuli will include electrical stimulation of cervical vagal afferents, pharmacological activation of vagal afferents, intravenous phenylephrine-induced increases in arterial blood pressure, and intravenous nitroprusside-induced decreases in arterial blood pressure. Tests of cardiopulmonary stimuli will be performed on both intact rats and rats with cardiopulmonary deafferentation. The specific aims of this proposal are to (1) quantitatively characterize the influence of either vagal or high pressure baroreceptor afferents on ON and OFF cells in the control of arterial blood pressure and the modulation of the nociceptive tail flick reflex, (2) quantitatively determine the contribution of the locus coeruleus/subcoeruleus and rostroventrolateral medulla to vagally- mediated changes in ON and OFF cells in spinopetal control of nociception, arterial blood pressure regulation, and visceral-visceral and visceral-somatic convergence.