ABSTRACT
<p><b>OBJECTIVE</b>To investigate the pathological changes of chronic intermittent hypoxia on upper and lower respiratory tissue in experimental rats.</p><p><b>METHODS</b>A total of 40 female SD rats were divided into 2 groups. Twenty rats were fed in normal state (control group), and 20 rats were fed in hypoxia environment (hypoxia group). The pathological changes of upper and lower respiratory tissue were observed under optical microscope.</p><p><b>RESULTS</b>Chronic intermittent hypoxia resulted in irreversible changes both at upper and lower respiratory tract in rats. The thickness of the lamina propria in soft palate was significantly increased in hypoxia group (125.85 ± 6.34) µm vs. (57.26 ± 4.67) µm (t=36.330, P<0.01). Lung pathological examination in hypoxia group showed pulmonary interval thickening (2.15 ± 0.49) µm vs. (0.45 ± 0.12) µm (t=14.132, P<0.01).</p><p><b>CONCLUSIONS</b>This study confirmed that long-term hypoxia can lead to organization reconstruction in upper and lower respiratory tract in rats. In OSAHS patients, it is suggested that earlier intervention could alliviate the pathological changes in respiratory system.</p>