Hu J, Song X, Li X, Tian N
Lab of Microcirculation, Chinese PLA General Hospital, Beijing.
Zhongguo Ying Yong Sheng Li Xue Za Zhi. 1997 Nov;13(4):352-5.
An intravital fluorescence microscopic method and digital image analysis were established for measuring the changes of fluorescein sodium (FINa, MW 376) and FITC-Dextrans (FD-4, MW4000, FD-150, MW150000) permeability in mesenteric microvessels. The transport of various molecular fluorescent tracer within the blood vessels and through the vessel walls into the perivascular tissue of the rat mesentery was studied using a highly sensitive CCD camera, the fluorescence intensities were transformed into video signals and recorded for subsequent analysis. The results showed that FINa could pass through the wall of microvessels very quickly. The diffusion constant was 3.362 x 10(-8) cm2/s with FINa, and FD-4 was 1.718 x 10(-8) cm2/s, FD-150 was 0.0486 x 10(-8) cm2/s. The diffusion constant depended very strongly on the molecular weight and showed no difference between capillary and vessels of the venous part of the microcirculation, but in vessels of the arterial part of microcirculation no diffusion was found. That was to say that diffusion occurred in capillary and microvenous, but not in microarterial. It is expected that this method would be very useful for the quantitive analysis in various molecular weights and in monolayer endothelial cell permeability.
建立了一种活体荧光显微镜方法和数字图像分析方法，用于测量荧光素钠（FINa，分子量376）和异硫氰酸荧光素标记葡聚糖（FD - 4，分子量4000，FD - 150，分子量150000）在肠系膜微血管中的通透性变化。使用高灵敏度的电荷耦合器件（CCD）相机研究了各种分子荧光示踪剂在大鼠肠系膜血管内以及通过血管壁进入血管周围组织的转运情况，荧光强度被转换为视频信号并记录下来以供后续分析。结果表明，FINa能够非常迅速地穿过微血管壁。FINa的扩散常数为3.362×10⁻⁸ cm²/s，FD - 4为1.718×10⁻⁸ cm²/s，FD - 150为0.0486×10⁻⁸ cm²/s。扩散常数非常强烈地依赖于分子量，并且在微循环静脉部分的毛细血管和血管之间没有差异，但在微循环动脉部分的血管中未发现扩散现象。也就是说，扩散发生在毛细血管和微静脉中，而不是在微动脉中。预计该方法对于各种分子量以及单层内皮细胞通透性的定量分析将非常有用。
