烧伤皮肤脂蛋白复合物诱导严重烧伤大鼠肺间质水肿的机理研究

目的：探讨烧伤皮肤脂蛋白复合物（LPC）对肺血管通透性的影响及其机理。方法：用30％Ⅲ度大鼠烧伤模型,提取外周血LPC;建立大鼠离体肺灌注技术;根据灌流液内容不同将实验动物分为4组：LPC组,烧伤血清组,正常血清组和对照组。测定灌流后5min和35min的肺重量增加（LWG）和液体滤过系数（Kf)及白蛋白通透性与表面积乘积（PS）。结果：（1）烧伤血清和LPC均能使LWG增加,以烧伤血清更为明显;（2）烧伤血清能使Kf和PS均增加,但以Kf的增加更为显著,LPC只能全程Kf增加而对PS无明显影响。烧伤血清对Kf的作用较LPC更为明显。结论：严重烧伤后,LPC具有诱发烧伤后肺水肿的作用,LPC可能介导或参与了烧伤后肺血管对小分子物质通透性的影响。

Effect of lipid protein complex on pulmonary vascular permeability in rats with severe burn

OBJECTIVE: To investigate the effect of lipid protein complex (LPC) from burn wound on the pulmonary vascular permeability. METHODS: Fifty-two SD rats were made into 30%III degrees TBSA burn models. Six milliliters of peripheral blood were extracted from each rat 3 days after and LPC was isolated. Then 32 rats were killed. Their lungs and hearts were isolated to be made into experimental model of isolated perfused heart and lung and divided into 4 experimental groups perfused with different kinds of perfusion fluid containing LPC, serum from rats with burn, serum from normal rats, or perfusion fluid without above mentioned components (control group). Five minutes and 35 minutes after the perfusion, the lung weigh gain (LWG), fluid filtration coefficient (Kf) and pulmonary albumin permeability-surface area product (PS) were detected. RESULTS: Five minutes after perfusion the LWG was 0.08 +/- 0.04 g in the burn serum group, and 0.07 +/- 0.04 g in the LPS group, both significantly higher than that in the control group (0.03 +/- 0.03, both P < 0.01). Thirty-five minutes after, the LWG was 0.56 +/- 0.12 g in the burn serum group, and 0.40 +/- 0.10 g in the LPS group, both significantly higher than that in the control group (0.26 +/- 0.08 g, P < 0.01) and with a significant difference between the burn serum group and LPC group (P < 0.05). PS was 7.6 +/- 1.3 x 10(-2) cm(3)/min x g DLW in the burn serum group, significantly higher than that in the control group (4.2 +/- 1.1 x 10(-2) cm(3)/min x g DLW, P < 0.01), and LPC group (4.6 +/- 1.2 2 x 10(-2) cm(3)/min x g DLW, P - 0.01), without a significant difference between the LPC and control group. Kf was 1.05 +/- 0.20 ml/min x kPa x g DLW in the burn serum group, and 0.89 +/- 0.13 ml/min x kPa x g DLW in the LPC group, both significantly higher than that in control group (0.32 +/- 0.09 ml/min x kPa x g DLW, P < 0.01) and with a significant difference between the burn serum group and LPC group (P < 0.05). No difference in LWG, PS, and Kf was found between normal serum group and control group. CONCLUSION: LPC from burn serum induces pneumonedema in severe burn animal and may play a role in increasing vascular permeability to small molecules.