Durham S K, Horan M A, Brouwer A, Barelds R J, Knook D L
TNO Institute for Experimental Gerontology, Rijswijk, The Netherlands.
J Pathol. 1989 Apr;157(4):339-45. doi: 10.1002/path.1711570411.
Recent studies have demonstrated that aged rats are more susceptible to the lethal effects of endotoxin as compared with young rats. The morphogenesis of early endotoxin-induced pulmonary injury in young (6 months) and aged (24 months) rats was examined by combined light and transmission electron microscopy to elucidate cell populations that may be responsible for these effects. Pulmonary endothelial cell injury was of greater severity and occurred at earlier time periods in aged rats as compared with young rats. Platelet sequestration and aggregation were observed only in aged rats in this study, and occurred in conjunction with the initial degenerative changes in the endothelium. Morphological evidence of granulocyte degranulation and fragmentation was also observed only in aged rats. These results suggest that pulmonary endothelial cells of aged rats are more susceptible to endotoxin-induced injury and that platelets may play an important role in the enhancement of initial endothelial damage. Furthermore, the extent of injury to the endothelial cell population may play an important role in accounting for differences in endotoxin-induced mortality between young and aged rats.
最近的研究表明，与年轻大鼠相比，老年大鼠对内毒素的致死作用更敏感。通过光学显微镜和透射电子显微镜联合检查年轻（6个月）和老年（24个月）大鼠早期内毒素诱导的肺损伤的形态发生，以阐明可能导致这些效应的细胞群。与年轻大鼠相比，老年大鼠的肺内皮细胞损伤更严重，且发生时间更早。在本研究中，仅在老年大鼠中观察到血小板扣押和聚集，并且与内皮的初始退行性变化同时发生。仅在老年大鼠中也观察到粒细胞脱颗粒和破碎的形态学证据。这些结果表明，老年大鼠的肺内皮细胞对内毒素诱导的损伤更敏感，并且血小板可能在增强初始内皮损伤中起重要作用。此外，内皮细胞群的损伤程度可能在解释年轻和老年大鼠内毒素诱导的死亡率差异方面起重要作用。
