Alyaudtin R N, Reichel A, Löbenberg R, Ramge P, Kreuter J, Begley D J
Department of Pharmacology, Sechnov Medical Academy, B. Pirogovskaja 2-6, 119881 Moscow, Russia.
J Drug Target. 2001 Jun;9(3):209-21. doi: 10.3109/10611860108997929.
Poly(butylcyanoacrylate) nanoparticles were produced by emulsion polymerisation and used either uncoated or overcoated with polysorbate 80 (Tween 80). [3H]-dalargin bound to nanoparticles overcoated with polysorbate 80 or in the form of saline solution was injected into mice and the brain concentrations of radioactivity determined. Statistically significant, three-fold higher brain concentrations with the nanoparticle preparations were obtained after 45 minutes, the time of greatest pharmacological response assessed as analgesia in previous experiments. In addition the brain inulin spaces in rats and the uptake of fluoresceine isothiocyanate labelled nanoparticles in immortalised rat cerebral endothelial cells, (RBE4) were measured. The inulin spaces after i.v. injection of polysorbate 80-coated nanoparticles were significantly increased by 1% compared to controls. This is interpreted as indicating that there is no large scale opening of the tight junctions of the brain endothelium by the polysorbate 80-coated nanoparticles. In in vitro experiments endocytic uptake of fluorescent nanoparticles by RBE4 cells was only observed after polysorbate 80-overcoating, not with uncoated particles. These results further support the hypothesis that the mechanism of blood-brain barrier transport of drugs by polysorbate 80-coated nanoparticles is one of endocytosis followed by possible transcytosis. The experiments were conducted in several laboratories as part of an EEC/INTAS collaborative program. For various procedural and regulatory reasons this necessitated the use of both rats and mice as experimental animals. The brain endothelial cell line used for the in vitro studies is the rat RBE4.
聚氰基丙烯酸丁酯纳米颗粒通过乳液聚合制备，可直接使用或用聚山梨酯80（吐温80）包衣。将与聚山梨酯80包衣的纳米颗粒结合的[³H] - 达乐argin或呈盐溶液形式的[³H] - 达乐argin注入小鼠体内，并测定脑中放射性浓度。在45分钟后，纳米颗粒制剂在脑中的浓度在统计学上显著提高了三倍，45分钟是先前实验中评估为镇痛的最大药理反应时间。此外，还测量了大鼠脑中的菊粉空间以及永生化大鼠脑内皮细胞（RBE4）对异硫氰酸荧光素标记纳米颗粒的摄取。静脉注射聚山梨酯80包衣纳米颗粒后，菊粉空间与对照组相比显著增加了1%。这被解释为表明聚山梨酯80包衣的纳米颗粒不会导致脑内皮紧密连接大规模开放。在体外实验中，仅在聚山梨酯80包衣后观察到RBE4细胞对荧光纳米颗粒的内吞摄取，未包衣的颗粒则未观察到。这些结果进一步支持了以下假设：聚山梨酯80包衣的纳米颗粒介导药物通过血脑屏障的机制是内吞作用之一，随后可能发生转胞吞作用。这些实验是作为欧洲经济共同体/国际科技合作计划的一部分在几个实验室进行的。由于各种程序和监管原因，这需要使用大鼠和小鼠作为实验动物。用于体外研究的脑内皮细胞系是大鼠RBE4。
