Suzuki M, Yamasoba T, Kaga K
Department of Otolaryngology, National Tohsei Hospital, Shizuoka, Japan.
Hear Res. 1998 Feb;116(1-2):107-12. doi: 10.1016/s0378-5955(97)00208-6.
Systemically administered cationic polyethyleneimine (PEI) passes through the capillary endothelial cell and attaches to anionic sites on the capillary basal lamina (BL). Thus, the distribution of PEI on the BL reflects the changes in the endothelial cell transport system. A 0.1% PEI solution was administered by intravenous injection (7.5 ml/kg) to developing (4, 7, 11, 14, 21 days after birth) and adult rats to evaluate the development of endothelial cell transport in the cochlear capillary as related to age. One hour later, the bony labyrinth was removed and embedded in Epoxy resin. Ultrathin sections of the cochlear lateral wall were then viewed with a transmission electron microscope. The distribution of PEI in the capillary BL in the stria vascularis of the 4-, 7- and 11-day-old rats was significantly greater compared to the adult rats. The distribution of PEI in the capillary BL in the spiral ligament of the 4- and 7-day-old rats was also significantly greater compared to the adult rats. These findings suggest that the endothelial cell transport is more robust in the developing rat cochlea and that the blood-labyrinth barrier becomes mature by 14 days after birth in rats.
全身给药的阳离子聚乙烯亚胺（PEI）穿过毛细血管内皮细胞，并附着在毛细血管基膜（BL）的阴离子位点上。因此，PEI在基膜上的分布反映了内皮细胞转运系统的变化。通过静脉注射（7.5毫升/千克）向发育中的（出生后4、7、11、14、21天）和成年大鼠给予0.1%的PEI溶液，以评估耳蜗毛细血管中内皮细胞转运的发育与年龄的关系。一小时后，取出骨迷路并嵌入环氧树脂中。然后用透射电子显微镜观察耳蜗外侧壁的超薄切片。与成年大鼠相比，4日龄、7日龄和11日龄大鼠血管纹中毛细血管基膜内PEI的分布明显更多。与成年大鼠相比，4日龄和7日龄大鼠螺旋韧带中毛细血管基膜内PEI的分布也明显更多。这些发现表明，发育中的大鼠耳蜗内的内皮细胞转运更强健，并且大鼠出生后14天血迷路屏障成熟。
