大鼠脑内组织通道对物质传递的性质研究

Study of Property of Substance Transference in Cerebral Tissue Channel in Rat

目的 :探讨大鼠脑内组织通道对物质传递的性质。方法 :建立并运用活体注射标记物连续冰冻切片法 ,将不同分子量的荧光标记物活体定位注入Wistar大鼠脑的不同部位。然后 ,以荧光团体积定量 ,比较荧光标记物扩散的形态范围的部位差异以及分子量差异 ,并与脑组织显微结构结合分析。结果 :荧光标记物首先沿神经纤维扩散 ,并可沿胼胝体到达对侧大脑 ,扩散的速度范围大于在皮质 ;小分子量的荧光素钠比大分子量的FITC标记右旋糖酐 (FD)在相同部位扩散的速度范围大 ,并且FD主要沿神经纤维扩散。结论 :在物质传递方面 ,神经纤维周围组织通道具有优势 ,脑组织通道对不同分子量物质具有选择性。这些性质的揭示不仅可为脑内肿瘤的局部化疗用药提供理论依据和在开发药物剂型方面有重要的参考意义 ;而且可有助于对容积传递 (volumetranmis sion)的深入研究。

Objective: To study the property of substance transference in cerebral tissue channel in rat.Method: The method of continuously cryostat sectioning after microinjection of fluorescence labelled substance in vivo was established and used.Substance with different molecular weight(MW) were microinjected into different part in the brain of wister rat.After diffusing,the difference of the form and range of fluorescence(quantified by volume of fluorescence mass) in different part and in different MW were observed.Fluorescent images were analysed with tissue structure.Results: Substance diffused primarily along nerve fibers and reached into contralateral brain through corpus callosum,resulted into larger range.Fluorescein sodium(with low MW)diffused easily in higher velocity and larger range than FITC labelled dextran(FD,with high MW),who diffused mainly in the dominant tissue channel.Conclusion: In substance transference,perinerve fiber tissue channel has dominance;cerebral tissue channel has the property of molecular selectivity.These functional property not only could provide theoretic basis for local applying of anticancer drugs and guide us to develop proper production,but also could help to sutdy the volume transmission in the brain.