The significance of Tumor necrosis factor-alpha and Tumor necrosis factor rceptor 1 in The rat model of COPD

Objective To investigate the significance of Tumor necrosis factor-alpha(TNF-α)and Tumor necrosis factor rceptor 1(TNFR1)in the pathogenesis of COPD.MethodsThe rats were divided into a normal control group and a COPD model group.The rat model of COPD was established by exposure to cigarette smoking.Total cell counts,neutrophil counts and neutrophil proportion in serum and bronchoalveolar lavage fluid(BALF)were examined.The lung function includes forced expiratory volume in 0.3 secend(FEV0.3)、forced expiratory volume in 0.3 secend vs forced vital capacity(FEV0..3/FVC%)and peak expiratory flow(PEF),pathologic changes of lung tissues were investigated.The mean linear intercept(MLI)and mean alveolar numbers(MAN)were determined by light microscope in order to study the degree of emphysema.The levels of TNF-α and TNFR1 in serum and BALF were measured with enzyme linked immunosorbent assay(ELISA).ResultsAfter modeling in COPD group comparing with normal group statistic analysis showed total leukocyte counts and neutrophil counts and neutrophil proportion were increased,FEV0.3(4.20±0.25)ml vs(1.86±0.22)ml,FEV0.3/FVC(85.56±5.85)% vs(65.06±8.40)%,PEF(47.24±7.28)ml/s vs(18.84±1.56)ml/s in normal group vs COPD group respectively.FEV0.3、FEV0.3/FVC and PEF were significantly decreased in COPD group comparing with normal group(P0.05),MLI(77.32±28.73)um/n vs(43.96±7.16)um/n in COPD group was higher than that in normal group while MAN(232.00±97.18)n/mm2 vs(392.84±24.41)n/mm2 was decreased in COPD group compared with normal group(P0.05).The levels of TNF-α in serum and BALF(73.98±16.41)pg/ml vs(79.20±27.70)pg/ml,(117.98±33.82)pg/ml vs 155.10±27.60pg/ml were higher in S group than in N group.The levels of TNFR1 in serum and BALF(58.82±24.57)pg/ml vs(61.89±26.25)pg/ml,(85.00±16.34)pg/ml vs(98.13±11.97)pg/ml were higher in S group than in N group(all P0.05).The levels of TNFR1 in BALF revealed positive correlation to MLI but negative correlation to MAN in COPD group.ConclusionIt may play an important role in the pathogenesis of COPD that TNF-α and TNFR1 are inflammatory mediators.