Role of pulmonary surfactant on lung ischemic preconditioningª²induced protection against lung ischemia reperfusion injury

    JIANG Tao, ZHANG Tao, CHENG Qingª²Shu

    Department of Thoracic Surgery, Tangdu Hospital, Fourth Military Medical University, Xi¬ðan 710038, China

    ¡¾Abstract¡¿ AIM: To investigate whether the pulmonary surfactant (PS) is involved in the protective effects of lung ischemic preconditioning (IPC) against lung ischemia reperfusion (I/R) injury. METHODS: In vivo I/R injury of rabbit was induced by blocking the hilum of left lung. The arterial partial pressure of oxygen (PaO2), lung permeability index, leucocyte count and neutrophils percentage in bronchoalveolar lavage fluid (BALF) were detected as indexes of lung injury. Total phospholipid (TPL), saturated phosphatidylcholine (SatPC) and total protein (TP) in the BALF were respectively measured by Bartlett method, Mason method and Lowry method. The activity of PS was presented by the ratio of SatPC/TP and SatPC/TLP. RESULTS: I/R injury markedly reduced the arterial oxygen pressure, which increased in IPC group (P<0.01). The lung permeability index, leucocyte count and neutrophils percentage in BALF of I/R group were significantly higher than those in control group, which markedly reduced in IPC group (P<0.01). The SatPC/TP(ng/g) and SatPC/TLP(%)in I/R group were 124¡À23 and 36.5¡À4.9, respectively, both significantly lower than those in control group (P<0.01). The two indexes in IPC group were 159¡À28 and 44.7¡À6.8, respectively, markedly higher than those in I/R group (P<0.01). CONCLUSION: Lung IPC has a remarkable protective effect against I/R injury. The effect is related to the maintaining of the content and activity of PS. ......