ABSTRACT
Objective To study the effect of platelet-derived growth factor(PDGF)and lysosomes on lung injury in macaque with early-phase endotoxie shock.Method Eleven macaques were randomly divided into two groups,namely,control group(Co group,n=5)iand endotoxic group(En group,n=6).The macaque of the Co group injected with 1 ml/kg normal saline and the macque of the En group received a dose of 2.8 mg/kg Lipopolysaccharides(LPS)i.v.The blood gas was detected at 120 minutes after LPS challenging. Uhrastructure,cytochemistry of acid phosphatase(ACPase)detection by electronic microscopy and immunohistochemical assay of PDGF were completed in hmgs of all the macaque .Results Administration of LPS did not change the parameters of gas exchange,namely,PaO_2,PaO_2/Fi and PaCO_2.In the early phase,of endotoxic shock,ACPase activity products increased and lysosome destroyed in the alveolar cells.The pathologic changes of alveolus,such as degeneration of vessel endothelium,injury of alveolar epithelium and damage of basement membrane,and transudation of blood component were observed by electron microscopy in the En group. However,no pathological changes were found in the control group.By immunohistochemical staining,PDGF on alveolar wall in the En animals was observed,whereas no PDGF protein in the Co macaques was noticed. Conclusions Administration of LPS induced the expression of PDGF in the alveolar wall and lysosome injury in the alveolar cells,as a result of alveolar damage in early-phase endotoxin shock.In the meantime,the parameters of gas exchanges did not change.The PDGF may play an important role in the pathogenesis of lung during the early-phase of endotoxin shock.