RESUMO
OBJECTIVE: To investigate whether acute lung injury (ALI) and changes of myocardial ATP enzymes were induced by intravenous or intraventricle of left heart injection of lipopolysaccharide (LPS) in aging rats. METHODS: 40 male Wistar rats were used for reproducing aging animal model. Aging rats were randomly divided into aging control group (n = 8), ALI group (LPS, 5 mg/kg body weight intravenous injection, n = 16), and LPS group (same dosage LPS, intraventricle of left heart injection, n = 16). The samples (blood, lung and heart) were collected at 2, 6 hours after LPS or saline administration. RESULTS: Compared with aging control, protein content in bronchial alveolar lavage fluid (BALF), ratio of lung wet/dry weight and the LA, NO2-/NO3- and MDA contents in blood were increased markedly (P < 0.01) at 2, 6 hours in ALI group. The GSH-Px, Na(+)-K(+)-ATPase activities in lung tissue were decreased significantly (P < 0.01), but NO2-/NO3- content in lung tissue was increased obviously (P < 0.01) at 2 hours in ALI group. These changes were maintained until at 6 hours after LPS administration. The above parameters were no obviously changes in myocardium at 2 hours after LPS administration in ALI group. But at 6 hours, MDA content was increased obviously (P < 0.01); Na(+)-K(+)-ATPase, Ca(2+)-Mg(2+)-ATPase and GSH-Px activities in myocardium were decreased markedly (P < 0.01). While in LPS group, only NO2-/NO3- contents were increased (P < 0.05) in blood and lung tissue as well as Na(+)-K(+)-ATPase activity in lung tissue were decreased (P < 0.05), another parameters had no obvious changes. CONCLUSIONS: ALI was obviously formed by intravenous injection LPS after 2, 6 hours in aging rats. Myocardial enzyme etc decreased only at 6 hours in ALI group. But above parameters were no obviously changes in LPS group. It was suggested that there was probable myocardial damage in rats of ALI group, and it was mainly induced by ALI.