REGULATION OF CEREBRAL BLOOD FLOW BY THE ROSTRAL VENTROLATERAL MEDULLA

这一持续项目的目标是调查 头侧皮层神经元 延髓腹外侧区（RVL）调节脑循环。 RVL神经元的兴奋提高局部脑血流量 脑血流（rCBF）在大脑皮质内，不升高大脑 新陈代谢. 这些神经元也介导了 脑血管舒张至缺氧。 三项研究将 结合了微电子和化学的联合收割机方法 刺激，神经元失活，生物电活动记录 和rCBF，以及束追踪和免疫细胞化学， 麻醉大鼠。 项目一将检验以下假设： 尾侧RVL中一组特殊神经元的兴奋 （B）这些RVLc升高大脑皮层中的rCBF; 神经元被FN、NTS和氧反射性地兴奋 RVL吻侧敏感神经元（RVLr）;（c）通往 RVLc的皮质是间接的，通过皮质下 投射可能局限于Z1;（d） Z1神经元RVLc的兴奋依赖于 皮质神经元升高rCBF的最终表达;（e） 在RVL中代表的血管舒张通路是常见的 FN、NTS和RVLr的激活也通过该途径 导致脑电图减慢和局部脑血流量升高 研究 将首次提供证据证明 脑干连接内脏传入活动与循环， 脑电活动

The objective of this continuing project is to investigate the mechanisms and pathway through which neurons in the rostral ventrolateral medulla (RVL) regulate the cerebral circulation. Excitation of neurons of the RVL elevates regional cerebral blood flow (rCBF) within the cerebral cortex without elevating cerebral metabolism. These neurons also mediate half of the cerebrovascular vasodilation to hypoxia. Three studies will be undertaken which combine methods of microelectrical and chemical stimulation, neuronal inactivation, recording of bioelectrical activity and rCBF, and tract tracing and immunocytochemistry in anesthetized rats. Project I will test the hypotheses that (a) excitation of a distinctive group of neurons in the caudal RVL (RVLc) elevates rCBF in the cerebral cortex; (b) these RVLc neurons are reflexively excited from FN, NTS, and oxygen sensitive neurons of rostral RVL (RVLr); (c) the pathway to the cortex from RVLc is indirect and relays through a subcortical projection probably localized to Zl; (d) vasodilatory effects of excitation of RVLc of Zl neurons depend upon the integrity of cortical neurons for the final expression of elevated rCBF; (e) the vasodilator pathway represented in the RVLs is the common pathway through which activation of FN, NTS, and RVLr also produces a slowing of the EEG and elevation of rCBF. The study will provide evidence for the first time of a full pathway of the brainstem linking visceral afferent activity with the circulation and electrical brain activity.