Morphological analysis of the respiratory tract of Wistar rats was performed after a single parenteral administration of 12-nm silicon dioxide nanoparticles (1 ml, 2 mg/ml, intravenously) was performed. On day 21 and in 2, 4, and 6 months after the administration of nanoparticles, the development of macrophage infiltration in the interstitium of the respiratory tract was demonstrated by histological and immunohistochemical methods. The pool of alveolar macrophages increased in 4 months after administration (p=0.004) and returned to the control values in 6 months. The number of mast cells did not significantly change at all stages of the experiment. Connective tissue remodeling in the interstitium of the respiratory tract was not observed throughout the observation period.

中文翻译：

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二氧化硅纳米颗粒胃肠外给药后大鼠呼吸道的形态学分析

在单次胃肠外给予 12 nm 二氧化硅纳米粒子（1 ml，2 mg/ml，静脉注射）后，对 Wistar 大鼠的呼吸道进行形态学分析。在纳米颗粒给药后第 21 天和第 2、4 和 6 个月，通过组织学和免疫组织化学方法证实了呼吸道间质中巨噬细胞浸润的发展。肺泡巨噬细胞池在给药后 4 个月内增加（p=0.004），并在 6 个月内恢复到对照值。肥大细胞的数量在实验的所有阶段都没有显着变化。在整个观察期内未观察到呼吸道间质中的结缔组织重塑。