Forearm neurovascular responses during mental stress and vestibular activation.
Forearm neurovascular responses during mental stress and vestibular activation.
复制标题
精神应激和前庭激活期间前臂神经血管反应。
DOI：
10.1152/ajpheart.00569.2004
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
Ray,ChesterA
中科院分区：
文献类型：
--
作者：
Carter,JasonR;Cooke,WilliamH;Ray,ChesterA
Autonomic responses may underlie associations among anxiety, vestibular dysfunction, and unexplained syncope. Mental stress (MS), an anxiety-inducing stimulus, causes forearm vasodilation, whereas the vestibulosympathetic reflex (VSR) causes forearm vasoconstriction. The purpose of this study was to examine the combined effects of mental and vestibular stimulation on neurovascular control in the forearm. Heart rate, arterial pressure (Finapres), and forearm blood flow (Doppler) were measured in 10 healthy volunteers in the prone position during1) head-down rotation (HDR),2) MS (mental arithmetic), and3) HDR + MS. Forearm vascular resistance (FVR) increased during HDR (from 232 ± 40 to 319 ± 53 units) and decreased during MS (from 260 ± 57 to 154 ± 22 units). During HDR + MS, FVR did not change [change (Δ) = −31 ± 50 units] and was not significantly different from the algebraic sum of each trial performed alone (Δ = −20 ± 42 units). Arm muscle sympathetic nerve activity (MSNA; microneurography) was measured in seven additional subjects. MSNA increased during HDR (from 13 ± 2 to 17 ± 2 bursts/min) and HDR + MS (from 11 ± 2 to 16 ± 2 bursts/min). Increases in MSNA during HDR + MS (Δ = 5 ± 2 bursts/min) were not different from the algebraic sum of each trial performed alone (Δ = 6 ± 2 bursts/min). We conclude that an additive neurovascular interaction exists between MS and the VSR in the forearm. Activation of the VSR prevented forearm vasodilation during MS, suggesting that activation of the VSR may help protect against stress-induced syncope.
