Physiological and Pathological Brain Activation in the Anesthetized Rat Produces Hemodynamic-Dependent Cortical Temperature Increases That Can Confound the BOLD fMRI Signal.
Physiological and Pathological Brain Activation in the Anesthetized Rat Produces Hemodynamic-Dependent Cortical Temperature Increases That Can Confound the BOLD fMRI Signal.
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DOI：
10.3389/fnins.2018.00550
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发表时间：
2018
影响因子：
4.3
通讯作者：
Berwick J
中科院分区：
文献类型：
--
作者：
Harris SS;Boorman LW;Das D;Kennerley AJ;Sharp PS;Martin C;Redgrave P;Schwartz TH;Berwick J
麻醉啮齿动物模型在临床前神经影像学研究中无处不在。然而，由于相关的大脑形态和实验方法导致了深刻的负脑-核心温差，功能激活期间的大脑温度变化可能主要由新鲜的、核心温度的血液的局部流入驱动。这对从这些模型中获得的血氧水平依赖性（BOLD）功能性磁共振成像（fMRI）数据的解释提出了混淆，因为该信号也是严格依赖于温度的。然而，以前对这个问题的调查是令人惊讶的稀疏。在这里，我们解决这个问题，通过使用一种新的多模式的方法在氨基甲酸乙酯麻醉大鼠。我们发现，感觉刺激，高碳酸血症和反复急性癫痫发作诱导皮质温度的显着增加，优先与总血红蛋白浓度（Hbt）的变化，相对于脑血流量和氧化代谢。此外，使用幻影为基础的评价，这种温度变化的影响BOLD功能磁共振成像信号，我们证明了一个强大的两个变量之间的反比关系。这些研究结果表明，温度升高，由于功能性充血，应占，以确保准确的解释BOLD功能磁共振成像信号在临床前的神经影像学研究。
Anesthetized rodent models are ubiquitous in pre-clinical neuroimaging studies. However, because the associated cerebral morphology and experimental methodology results in a profound negative brain-core temperature differential, cerebral temperature changes during functional activation are likely to be principally driven by local inflow of fresh, core-temperature, blood. This presents a confound to the interpretation of blood-oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) data acquired from such models, since this signal is also critically temperature-dependent. Nevertheless, previous investigation on the subject is surprisingly sparse. Here, we address this issue through use of a novel multi-modal methodology in the urethane anesthetized rat. We reveal that sensory stimulation, hypercapnia and recurrent acute seizures induce significant increases in cortical temperature that are preferentially correlated to changes in total hemoglobin concentration (Hbt), relative to cerebral blood flow and oxidative metabolism. Furthermore, using a phantom-based evaluation of the effect of such temperature changes on the BOLD fMRI signal, we demonstrate a robust inverse relationship between both variables. These findings suggest that temperature increases, due to functional hyperemia, should be accounted for to ensure accurate interpretation of BOLD fMRI signals in pre-clinical neuroimaging studies.
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影响因子：
3.3
作者：
Collins, CM;Smith, MB;Turner, R
通讯作者：
Turner, R
影响因子：
64.8
作者：
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连续二元纳米合金的相图：尺寸、形状和偏析效应
影响因子：
4.6
作者：
Cui M;Lu H;Jiang H;Cao Z;Meng X
通讯作者：
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影响因子：
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作者：
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通讯作者：
Berwick J
影响因子：
3.3
作者：
Kennerley, AJ;Berwick, J;Mayhew, JE
通讯作者：
Mayhew, JE