Wang W, Hou J, Huang W Q
Department of Radiology, The First People's Hospital of Foshan, Foshan 528000, Guangdong, China.
Department of Radiology, The Second Affiliated Hospital of Guangzhou Medical University, Guangzhou 510260, China.
Beijing Da Xue Xue Bao Yi Xue Ban. 2019 Apr 18;51(2):206-209. doi: 10.19723/j.issn.1671-167X.2019.02.002.
To investigate the changes of brain interstitial fluid (ISF) induced by movement.
Twenty mature male Sprague-Dawley rats were randomly divided into two groups: control group and movement group. Electrophysiological neurons in caudate nuclear of additional five rats were recorded and the differences analyzed between under anesthesia and by movement. In the control group, the rats were anesthetized using isoflurane continuously during the experiment process. In the meantime the magnetic tracer was injected into the center of the caudate nucleus and multi-period magnetic resonance scanning was performed at several time points until high signal intensity invisible in the images. In the movement group, the rats were anesthetized for the injection of the tracer, and the first post-injection magnetic resonance scanning was performed. Then the rats were waken and allowed moving voluntarily for 20 minutes. The rats were anesthetized again and multi-period magnetic resonance scanning was performed until the experiment ended. NanoDetect system (Version 1.2, MRI lab, Beijing, China) was used to measure the parameters on ISF, which included the weighed signal intensity (weighed ΔSI) , the term predicting the amount of the tracer, and half-time of the tracer. In movement group, the weighed ΔSI at the time points of pre-movement and 10, 40, 70, 130, and 190 minutes after movement were calculated respectively. In control group, the weighed ΔSI at the same time points also were measured. The weighed ΔSI and half-time were compared between the two groups.
The electrophysiological recording and data analysis showed significant difference in the local field potential of Caudate Nucleus between under anesthesia and by movement. The weighed ΔSI (unit: ΔSI×mm) values of the two groups, presented by movement group vs. control group, were as followings, 60 257.1±23 069.2 vs. 61 072.0±19 547.3 at pre-move, 83 624.3±21 475.7 vs. 71 218.1±12 586.5 at 10 min after movement, 57 336.0±36 243.4 vs. 69 756.1±13 306.0 at 40 min after movement, 43 705.9±10 246.3 vs. 55 443.2±20 733.3 at 70 min after movement, 7 734.9±2 645.2 vs. 8 967.6±2 007.3 at 130 min after movement and 2 497.3±987.5 vs. 3 013.2±1 760.8 at 190 min after movement. Moreover, at 40 min after movement, the weighed ΔSI of movement group was significantly reduced compared with control group (P<0.05). The half-time was not significantly different [(104.3±54.1) min vs. (113.4±47.3) min, P>0.05].
ISF drainage of caudate nuclear can be acclerated temporarily by movement.
研究运动引起的脑间质液（ISF）变化。
将20只成年雄性Sprague-Dawley大鼠随机分为两组：对照组和运动组。另外记录5只大鼠尾状核的电生理神经元，并分析麻醉状态下和运动状态下的差异。对照组在实验过程中持续使用异氟烷麻醉大鼠。同时，将磁性示踪剂注入尾状核中心，并在多个时间点进行多期磁共振扫描，直至图像中高信号强度不可见。运动组大鼠麻醉后注射示踪剂，进行首次注射后磁共振扫描。然后将大鼠唤醒，使其自主活动20分钟。之后再次麻醉大鼠并进行多期磁共振扫描直至实验结束。使用NanoDetect系统（版本1.2，中国北京MRI实验室）测量ISF的参数，包括加权信号强度（加权ΔSI）、预测示踪剂含量的指标以及示踪剂的半衰期。在运动组中，分别计算运动前以及运动后10、40、70、130和190分钟时间点的加权ΔSI。在对照组中，也测量相同时间点的加权ΔSI。比较两组的加权ΔSI和半衰期。
电生理记录和数据分析显示，麻醉状态下和运动状态下尾状核局部场电位存在显著差异。两组的加权ΔSI（单位：ΔSI×mm）值，运动组与对照组比较如下：运动前为60257.1±23069.2 vs. 61072.0±19547.3；运动后10分钟为83624.3±21475.7 vs. 71218.1±12586.5；运动后40分钟为57336.0±36243.4 vs. 69756.1±13306.0；运动后70分钟为43705.9±10246.3 vs. 55443.2±20733.3；运动后130分钟为7734.9±2645.2 vs. 8967.6±2007.3；运动后190分钟为2497.3±987.5 vs. 3013.2±1760.8。此外，运动后40分钟，运动组的加权ΔSI与对照组相比显著降低（P<0.05）。半衰期无显著差异[（104.3±54.1）分钟 vs. （113.4±47.3）分钟，P>0.05]。
运动可暂时加速尾状核的ISF引流。
