The Experimental Study Of TLR4 In Chronic Intermittent Hypoxia Induced By Sleep Apnea Hypopnea Syndrome

Objective:To observe the effects of intermittent hypoxia on lung tissue, then to investigate the Toll like receptor 4(TLR-4) in pulmonary inflammation caused by chronic intermittent hypoxia.Methods:24 healthy male Wistar rats(weight 220-250 g rats aged 10 weeks) were divided into three groups by random number table method: normal control group, intermittent hypoxia 4 weeks group, intermittent hypoxia 6 weeks group. All animal models were executed in the fourth week and sixth week after experiment. Separate the lung tissue of all rats. Observation under optical microscope in each group of lung tissue hematoxylin vitamin eosin(HE) staining after morphological changes;immunohistochemical method(SABC) was used to detecte the TLR-4 expression of rat lung tissue.Results:1. Under the microscope 4W hypoxic group and 6W hypoxic group showed alveolar expansion, alveolar septal thickening. The adjacent alveolar fusion to form a larger cavity but the 6W hypoxic group was more obvious than the 4W hypoxic group.2. Compared with the normal control group,the mean lining interval of(MLI)alveolar of the 4 W hypoxic group and 6W hypoxic group got thickening(P < 0.05),alveolar damage index(DI) increased(P < 0.05). the 6W hypoxic group is more obvious than 4W hypoxic group.3. Compared with normal control group, the expression of TLR4 in 4,6W hypoxic group were significantly higher, the difference was statistically significant(P<0.05).4. The expression of TLR4 in the 6W hypoxic group was higher than 4W hypoxic group(p <0.05), the difference was statistically significant(P < 0.05).Conclusion:1. Intermittent hypoxia can lead to the changes of alveolar expansion and alveolar septal thickening.2. The TLR-4 receptor is involved in lung inflammation caused by intermittent hypoxia, With the prolonged of hypoxia the expression of Tlr4 was increased.