ARTERIAL COMPRESSION OF THE VENTROLATERAL MEDULLA

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 延髓腹侧橄榄后沟的动脉压迫(S)在交感神经介导性(神经源性)高血压中起作用。 具体目标： 1.第一项研究的主要目标是生成沿延髓腹外侧表面(VLMS)产生对刺激(前3年)产生升压反应的位置的“正常”地图： 更具体地说，VLMS的升压敏感区将在后颅窝手术中使用直接电刺激进行标测。这些区域的位置将被记录，即映射到磁共振图像(MRI)上。有证据表明，这些区域可能对电刺激和动脉压迫都有类似的反应。电刺激VLMS对交感神经张力和心血管参数(全身血压(BP)、心率(HR)和动脉壁顺应性)的直接影响将被量化。交感神经张力将通过测量肌肉交感神经活动(MSNA)和血浆去甲肾上腺素来量化。 2.我们计划显示MRI显示的VLMS升压敏感区的明显动脉压迫(基于第一个研究中的“正常”地图)与交感神经依赖性升高的血压(神经源性高血压)之间的关联。(最近两年)： 在一组单独的高血压患者中，这项研究的次要目标将是确定高血压患者的神经源性激活模式是否与在相同解剖位置进行电刺激的高血压患者的神经源性激活模式相似。神经血管压迫患者的研究结果将是 与电刺激VLMS中类似部位时获得的神经源性和血流动力学反应的模式(来自第一项研究)进行比较。这些研究将有助于将VLMS急性电刺激引起的升压反应与血管压迫脑干相同解剖部位的患者产生持续性高血压的机制联系起来。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Arterial compression of area(s) along the retro-olivary sulcus of the ventro-lateral medulla has a role in sympathetically mediated (neurogenic) hypertension. Specific Aims: 1. The primary objective of the first study is to generate a 'normal' map of the locations along the ventro-lateral medullary surface (VLMS) that produce pressor responses to stimulation (First 3 years): More specifically, the pressor-sensitive regions of the VLMS will be mapped using direct electrical stimulation during posterior fossa surgery. The location of such areas will be recorded, i.e., mapped, onto magnetic resonance images (MRI). Evidence suggests that these areas may be similarly responsive to both electrical stimulation and arterial compression. The direct effects of electrical stimulation of the VLMS on sympathetic tone and cardiovascular parameters (systemic blood pressure (BP), heart rate (HR), and arterial wall compliance) will be quantified. Sympathetic tone will be quantified by measuring muscle sympathetic nerve activity (MSNA) and plasma norepinephrine. 2. We plan to show an association between MRI evident arterial compression of pressor-sensitive areas of the VLMS (based on the 'normal' map in the first study) and sympathetic dependency of elevated BP (neurogenic hypertension). (Last 2 years): In a separate group of subjects with essential hypertension, A secondary aim in this study will be to determine if the patterns of neurogenic activation are similar in hypertensive patients with arterial compression of the VLMS and in normotensive subjects with electrical stimulation of the same anatomic locations. The findings in patients with neurovascular compression will be compared with the patterns of neurogenic and hemodynamic responses obtained during electrical stimulation of similar sites in the VLMS (from the first study). These studies will be useful in linking mechanisms underlying the pressor response to acute electrical stimulation of the VLMS with those producing sustained hypertension in patients with vascular compression of the same anatomic sites of the brainstem.