CARDIOPULMONARY/SOMATIC INPUT TO MEDULLARY ON/OFF CELLS

最近的研究表明，假定的疼痛调节神经元（ON 和OFF细胞）接受心肺 输入并可调节动脉血压以及伤害感受。 因此，本提案的总体目标是， 电生理学研究定量描述了 ON和OFF细胞在脊髓伤害性感受和动脉 血压. 这将通过确定 心肺和躯体输入到这些神经元的会聚， 将神经活动的变化与动脉血的变化联系起来 压力和伤害感受。 躯体刺激包括无害的触摸， 有害的挤压和有害的辐射热 心脏刺激会 包括颈部迷走神经传入电刺激， 迷走神经传入的药理学激活，静脉内 苯肾上腺素诱导的动脉血压升高，以及 静脉注射硝普钠引起的动脉血压下降。 将对两只完整大鼠进行心肺刺激试验 和心肺传入神经阻滞的大鼠。 本建议的具体目标是：（1）从数量上 描述迷走神经或高压压力感受器的影响 ON和OFF细胞上的传入在动脉血压控制中的作用 以及伤害性甩尾反射的调制，（2） 定量地确定基因座的贡献 蓝斑/蓝斑下核和延髓头腹外侧区到迷走神经- 介导的ON和OFF细胞的变化， 伤害感受、动脉血压调节和内脏-内脏 和内脏-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.