Department of Neurology, School of Medicine, Keio University, Shinjuku-ku, Tokyo, Japan.
Microcirculation. 2012 Feb;19(2):166-74. doi: 10.1111/j.1549-8719.2011.00143.x.
To examine changes in red blood cell (RBC) velocity in intraparenchymal capillaries of rat cerebral cortex in response to KCl-induced cortical spreading depression (CSD).
In isoflurane-anesthetized rats, the velocity of fluorescently labeled RBCs flowing in capillaries in layer I was measured with a high-speed camera laser-scanning confocal fluorescence microscope, with simultaneous monitoring of DC potential, the electroencephalogram (EEG), partial pressure of oxygen (PO(2) ), and cerebral blood flow (CBF).
After KCl application, a transient deflection of DC potential (i.e., CSD) repeatedly appeared concomitantly with depression of EEG, and was propagated in the distal direction. PO(2) transiently decreased and CBF was slowly elevated. The frequency distribution of RBC velocity was shifted downward during CSD and was still low after the passage of CSD. When we observed RBC velocity in 38 individual capillaries, 10 capillaries exhibited slowed-down RBC during CSD and RBC velocity remained low in 2 even after the passage of CSD. On the other hand, RBCs with moderately (<3 mm/sec) or remarkably (>3 mm/sec) increased velocities were seen in 10 and 5 capillaries, respectively.
CSD-induced excitation of neurons may sustainably decrease or greatly increase RBC velocity in capillaries.
观察氯化钾诱导的皮质扩散性抑制（CSD）过程中，大鼠大脑皮层脑实质内毛细血管中红细胞（RBC）速度的变化。
在异氟烷麻醉的大鼠中，使用高速相机激光扫描共聚焦荧光显微镜测量 I 层中荧光标记 RBC 在毛细血管中的速度，同时监测 DC 电势、脑电图（EEG）、氧分压（PO₂）和脑血流（CBF）。
应用 KCl 后，DC 电势的短暂偏转（即 CSD）反复出现，同时伴有 EEG 抑制，并向远端传播。PO₂ 短暂降低，CBF 缓慢升高。CSD 期间 RBC 速度的频率分布向下移动，CSD 通过后仍保持较低水平。当我们观察 38 个单个毛细血管中的 RBC 速度时，10 个毛细血管在 CSD 期间表现出 RBC 速度减慢，甚至在 CSD 通过后 2 个毛细血管中的 RBC 速度仍保持较低水平。另一方面，在 10 个和 5 个毛细血管中分别观察到 RBC 速度中度（<3mm/sec）或显著（>3mm/sec）增加。
CSD 诱导的神经元兴奋可能持续降低或大大增加毛细血管中的 RBC 速度。
