Effects of lipopolysaccharide on aquaporin-1 expression and function in rat lung microvessel endothelial cells

AIM: To determine if aquaporin-1 (AQP-1) expression and function is influenced after lipopolysaccharide (LPS) stimulation in rat lung microvessel endothelial cells and to investigate the mechanisms of lung fluid abnormal metabolism in acute lung injury. METHODS: LPS at different concentrations (100 μg/L, 1 mg/L or 10 mg/L) was used to stimulate cultivated rat lung microvessel endothelial cells in vitro at different stimulatory times (4 h, 12 h or 24 h), respectively. Tritium water permeation was conducted for determining the intracellular signal intensity in rat lung microvessel endothelial cells. The RT-PCR technique was applied for the assay of the expression of AQP-1 mRNA. RESULTS: The signal intensity of intracellular tritium water in the LPS stimulation group was less than that in normal control significantly. Compared with the normal control group (P<0.01), there was obvious decrease in the expression of AQP-1 mRNA in LPS stimulation groups. CONCLUSION: The decreased expression of AQP-1 mRNA and the weaken function of transporting water suggest that AQP-1 may play a major role in abnormal fluid transportation in acute injured lung.