ABSTRACT
Objective To observe the immunohistochemical changes of ICAM-1,MMP-2 and MMP-9 in the lungs of immunocompromised rats with Pseudomonas aeruginosa pneumonia and their relationships with lung inflammation.Methods After the establishment of pseudomonas aeruginosa pneumonia infected immunocompromised rat mode,the pathological changes of lungs were observed, lung wet/dry ratios and total protein concentration in bronchial alveolar lavage fluid were tested,and imunnohistochemical study of ICAM-1,MMP-2 and MMP 9 in lung tissue were performed.Results 1.The staining intensity of ICAM-1 in alveolar epithelial cells turned stronger in rats with pulmonary infection than those without of both groups(P＜0.05);2.The staining intensity of MMP-2 in lung tissue was stronger in rats with pulmonary infection than those without infection in both groups,and reached peak at 6～9 h after inoculation.Immunohistochemical changes of MMP-9 exhibited a similar pattern,4.Immunohistochemical changes of ICAM-1,MMP-2 and MMP-9 showed some correlation with numbers of polymorphonuclears in lung tissue(P＜0.05);5.A correlation between the stai- ning intensity of MMP-9 in bronchial epithelial eells and total protein concentrations were observed(r_s =0.484,P＜0.05),similar association were found between the staining intensity of MMP-2 in alveolar epithelial cells,endothelium of arterioles and venules and tissues beneath endothelium and to- tal protein eoncentrations in bronchial alveolar lavage fluid(r_s were 0.457,0.492 and 0.429,respec- tively,P＜0.05).Conclusion In immunocompromised rats,the staining intensity of ICAM-1, MMP-2 and MMP-9 in lung tissue of those with pseudomonas aeruginosa pneumonia were stronger than those without infection,and the changes were demonstrated some correlation with the levels of polymorphonuclears infiltration or severity of lung injury.