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.