Prolonged exercise induces angiogenesis and increases cerebral blood volume in primary motor cortex of the rat
Prolonged exercise induces angiogenesis and increases cerebral blood volume in primary motor cortex of the rat
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DOI：
10.1016/s0306-4522(02)00664-4
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发表时间：
2003-01-01
期刊：
影响因子：
3.3
通讯作者：
Greenough, WT
中科院分区：
文献类型：
--
作者：
Swain, RA;Harris, AB;Greenough, WT
在成年大鼠长时间运动后，在三个独立的实验中检查了运动皮层毛细血管结构和功能的可塑性变化。前两个实验采用T-2-星星（T-2*）加权和流动交替反转恢复（FAIR）功能磁共振成像，以评估慢性变化的血容量和流量作为一个结果的运动。第三个实验使用针对在发育中的毛细血管上表达的CD 61整联蛋白的抗体来确定运动皮层毛细血管是否经历结构修饰。在实验1中，T-2* 加权图像的前肢区域的运动皮层获得后30天的重复活动或相对不活动的车轮上。质子信号强度显着降低运动动物的运动皮层与对照组相比。这种减少不是由于血管铁水平的改变。因此，这些结果与运动皮层前肢区域的毛细血管灌注或血容量增加最一致。FAIR图像在实验2中获得normocapnic和hypercapnic条件下表明，静息脑血流量在正常条件下没有改变，但在响应高水平的CO2升高，这表明，长时间的运动增加毛细血管储备的大小。最后，免疫组织学数据表明，运动在运动方案开始的30天内诱导毛细血管的稳健生长（血管生成）。对其他区域的分析未能发现灌注或毛细血管结构的任何变化，这表明这种运动活动诱导的可塑性可能是特定于运动cortex.These数据表明，毛细血管生长发生在运动区的大脑皮层作为一个强大的适应长期的运动活动。除了毛细血管生长，血管系统在激活条件下也经历了增强的流动。这些变化是慢性的，即使在麻醉的动物中也可观察到，并且可以使用非侵入性技术进行测量。(C)2003年IBRO。由爱思唯尔科技有限公司出版。保留所有权利。
Plastic changes in motor cortex capillary structure and function were examined in three separate experiments in adult rats following prolonged exercise. The first two experiments employed T-two-star (T-2*)-weighted and flow-alternating inversion recovery (FAIR) functional magnetic resonance imaging to assess chronic changes in blood volume and flow as a result of exercise. The third experiment used an antibody against the CD61 integrin expressed on developing capillaries to determine if motor cortex capillaries undergo structural modifications. In experiment 1, T-2*-weighted images of forelimb regions of motor cortex were obtained following 30 days of either repetitive activity on a running wheel or relative inactivity. The proton signal intensity was markedly reduced in the motor cortex of exercised animals compared with that of controls. This reduction was not attributable to alterations of vascular iron levels. These results are therefore most consistent with increased capillary perfusion or blood volume of forelimb regions of motor cortex. FAIR images acquired during experiment 2 under normocapnic and hypercapnic conditions indicated that resting cerebral blood flow was not altered under normal conditions but was elevated in response to high levels of CO2, suggesting that prolonged exercise increases the size of a capillary reserve. Finally, the immunohistological data indicated that exercise induces robust growth of capillaries (angiogenesis) within 30 days from the onset of the exercise regimen. Analysis of other regions failed to find any changes in perfusion or capillary structure suggesting that this motor activity-induced plasticity may be specific to motor cortex.These data indicate that capillary growth occurs in motor areas of the cerebral cortex as a robust adaptation to prolonged motor activity. In addition to capillary growth, the vascular system also experiences heightened flow under conditions of activation. These changes are chronic and observable even in the anesthetized animal and are measurable using noninvasive techniques. (C) 2003 IBRO. Published by Elsevier Science Ltd. All rights reserved.