Predicting Vessel Diameter Changes to Up-Regulate Biphasic Blood Flow During Activation in Realistic Microvascular Networks.
Predicting Vessel Diameter Changes to Up-Regulate Biphasic Blood Flow During Activation in Realistic Microvascular Networks.
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DOI：
10.3389/fphys.2020.566303
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发表时间：
2020
影响因子：
4
通讯作者：
Jenny P
中科院分区：
文献类型：
--
作者：
Epp R;Schmid F;Weber B;Jenny P
密集的血管网络将血液分配到大脑的不同区域。为了满足神经元活动变化引起的临时和空间变化的能量需求，血管系统能够局部上调血液供应。然而，不同血管类型的直径变化在多大程度上促进了上调，以及它们变化的空间和时间特征目前尚不清楚。在这里，我们提出了一种新的模拟方法，它解决了一个反问题来计算实现微血管网络中预定义的血流分布所需的单个血管的直径变化。这使我们能够系统地比较不同船型在各种监管情景中的影响。此外，该方法的优点在于，它处理了由于跟踪单个红细胞的运动而产生的血液流动的随机性质。由于反问题是关于时间平均压力和流量的，因此使用了一种确定性的方法来计算直径变化，这使得我们可以将该方法应用于具有高维参数空间的大型现实微血管网络。我们在人工和现实微血管网络中获得的结果表明，毛细血管水平上的直径变化能够非常局部化地调节血流。在只允许较大血管(即小动脉)适应的情况下，流量增加不能局限于特定的激活区域，而流量变化会扩散到邻近区域。此外，所有血管类型的相对较小的扩张和收缩都会导致毛细血管血流分布的实质性变化。这表明，为了获得局部的血流量增加，小规模的调节是必要的。
A dense network of blood vessels distributes blood to different regions of the brain. To meet the temporarily and spatially varying energy demand resulting from changes in neuronal activity, the vasculature is able to locally up-regulate the blood supply. However, to which extent diameter changes of different vessel types contribute to the up-regulation, as well as the spatial and temporal characteristics of their changes, are currently unknown. Here, we present a new simulation method, which solves an inverse problem to calculate diameter changes of individual blood vessels needed to achieve predefined blood flow distributions in microvascular networks. This allows us to systematically compare the impact of different vessel types in various regulation scenarios. Moreover, the method offers the advantage that it handles the stochastic nature of blood flow originating from tracking the movement of individual red blood cells. Since the inverse problem is formulated for time-averaged pressures and flow rates, a deterministic approach for calculating the diameter changes is used, which allows us to apply the method for large realistic microvascular networks with high-dimensional parameter spaces. Our results obtained in both artificial and realistic microvascular networks reveal that diameter changes at the level of capillaries enable a very localized regulation of blood flow. In scenarios where only larger vessels, i.e., arterioles, are allowed to adapt, the flow increase cannot be confined to a specific activated region and flow changes spread into neighboring regions. Furthermore, relatively small dilations and constrictions of all vessel types can lead to substantial changes of capillary blood flow distributions. This suggests that small scale regulation is necessary to obtain a localized increase in blood flow.
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影响因子：
16.2
作者：
Goense J;Merkle H;Logothetis NK
通讯作者：
Logothetis NK
影响因子：
6.3
作者：
Lee, Jonghwan;Wu, Weicheng;Boas, David A.
通讯作者：
Boas, David A.
影响因子：
2.9
作者：
Chen, J. Jean;Pike, G. Bruce
通讯作者：
Pike, G. Bruce
周细胞变性导致神经血管解偶联并限制大脑的供氧
影响因子：
25
作者：
Kisler K;Nelson AR;Rege SV;Ramanathan A;Wang Y;Ahuja A;Lazic D;Tsai PS;Zhao Z;Zhou Y;Boas DA;Sakadžić S;Zlokovic BV
通讯作者：
Zlokovic BV
影响因子：
25
作者：
Blinder, Pablo;Tsai, Philbert S.;Kaufhold, John P.;Knutsen, Per M.;Suhl, Harry;Kleinfeld, David
通讯作者：
Kleinfeld, David