ObjectiveTo investigate the expression of histone deacetylase 2 (HDAC2) in animal model of benign tracheal stenosis, and explore the mechanism of HDAC2 in development of tracheal stenosis.MethodsEighteen rabbits were randomly divided into a blank control group, a model group, and an erythromycin group, with 6 rats in each group. The model group and the erythromycin group underwent tracheostomy, the inner wall of trachea was brushed back and forth with a nylon brush for more than 20 times to induce benign tracheal stenosis. From 7 days before surgery to 9 days after surgery, the model group received gavage with saline, the erythromycin group received gavage with low-dose erythromycin in dose of 15 mg·kg–1·d–1, and the control group did not receive any treatment. On the 10th day after operation, all the rabbits were sacrificed and the trachea was cut to measure the tracheal stenosis. RNA and protein were extracted from the granulation tissue in the stenosis and the relative mRNA expressions of HDAC2, interleukin (IL)-6 and IL-8 in the granulation tissue were detected by real-time fluorescence quantitative PCR. The relative expression of HDAC2 protein was detected by Western blot.ResultsCompared with the blank control group, the tracheal stenosis in the model group was more obvious [(84.60±1.14)% vs.(27.00±6.44)%], the mRNA and protein expressions of HDAC2 were decreased (0.29±0.07 vs. 1.00±0.00, 0.20±0.02 vs. 0.49±0.04), the mRNA expressions of IL-6 and IL-8 were up-regulated (4.22±0.67 vs. 1.00±0.00, 162.72±23.23 vs.1.00±0.00). Compared with the model group, tracheal stenosis in the erythromycin group was relieved [(64.00±12.25)% vs. (84.60±1.14)%], the mRNA and protein expressions of HDAC2 were increased (0.42±0.14 vs. 0.29±0.07, 0.43±0.01 vs. 0.20±0.02), the mRNA expressions of IL-6 and IL-8 were decreased (0.72±0.24 vs. 4.22±0.67, 130.22±7.93 vs. 162.72±23.23). All the differences were statistically significant (all P<0.05). The Pearson correlation coefficient between tracheal stenosis and HDAC2 mRNA relative expression was –0.96 (P<0.05).ConclusionsThe down-regulation of HDAC2 expression in model of benign tracheal stenosis is related to the occurrence and development of tracheal stenosis. The low dose of erythromycin may be used to treat benign tracheal stenosis by up-regulating expression of HDAC2 and thus inhibiting the inflammatory disorder during tracheal injury repair.