Real-time imaging of cortical and subcortical control of muscle sympathetic nerve activity in awake human subjects

作     者：James, Cheree Macefield, Vaughan G. Henderson, Luke A. 

作者机构：Univ Western Sydney Sch Med Penrith NSW 1797 Australia Neurosci Res Australia Sydney NSW Australia Univ Sydney Dept Anat & Histol Sydney NSW 2006 Australia 

出 版 物：《NEUROIMAGE》 (神经图像)

年 卷 期：2013年第70卷

页      面：59-65页

核心收录：

学科分类：1002[医学-临床医学] 1001[医学-基础医学(可授医学、理学学位)] 1010[医学-医学技术（可授医学、理学学位）] 1009[医学-特种医学] 10[医学] 

基　　金：National Health and Medical Research Council of Australia 

主　　题：Sympathetic activity fMRI Microneurography 

摘      要：Blood pressure is controlled on a beat-to-beat basis through fluctuations in heart rate and the degree of sympathetically-mediated vasoconstriction in skeletal muscles. By recording muscle sympathetic nerve activity (MSNA) at the same time as performing functional magnetic resonance imaging (DM) of the brain, we aimed to identify cortical structures involved in central cardiovascular control in awake human subjects. Spontaneous bursts of MSNA were recorded via a tungsten microelectrode inserted percutaneously into the peroneal nerve of 14 healthy subjects in a 3 T MRI scanner. Blood Oxygen Level Dependent (BOLD) contrast - gradient echo, echo-planar - images were continuously collected in a 4 s ON, 4 s OFF sampling protocol. MSNA burst amplitudes were measured during the OFF periods and BOLD signal intensity was measured during the subsequent 4 s period to allow for neurovascular coupling and nerve conduction delays. Group analysis demonstrated regions showing fluctuations in BOLD signal intensity that covaried with the intensity of the concurrently recorded bursts of MSNA. Signal intensity and MSNA were positively correlated in the left mid-insula, bilateral dorsolateral prefrontal cortex, bilateral posterior cingulate cortex and bilateral precuneus. In addition, MSNA covaried with signal intensity in the left dorsomedial hypothalamus and bilateral ventromedial hypothalamus (VMH). Construction of a functional connectivity map revealed coupling between activity in VMH and the insula, dorsolateral prefrontal cortex, precuneus, and in the region of the left and right rostroventrolateral medulla (RVLM). This suggests that activity within suprabulbar regions may regulate resting MSNA by projections to the premotor sympathetic neurons in the rostroventrolateral medulla. Crown Copyright (c) 2013 Published by Elsevier Inc. All rights reserved.