The Preliminary Study Of Chronic Intermittent Hypoxia On Aorta Of Rats And Correlated Mechanism

ObjectObstructive sleep apnea hypopnea syndrome (OSAHS) is a potentially dangerous disease, the incidence rate of 2% to 4% higher incidence in the elderly. OSAHS is close to coronary heart disease, hypertension and atheroscleros. Chronic intermittent hypoxia is one of the main pathogenic mechanism. It has been found that chronic intermittent hypoxia can lead to abnormal lipid metabolism, lipid metabolic disorders and cardiovascular disease which are closely related to chronic intermittent hypoxia at home and abroad on lipid metabolism. Influence of rare, no similar studies reported. This study was to SD rats by chronic intermittent hypoxia and chronic continuous hypoxia intervention of inflammatory factors and chronic intermittent hypoxia and lipid metabolism, a preliminary study of chronic intermittent hypoxia on lipid metabolism in mechanisms, for the prevention and treatment lipid metabolism caused by OSAHS providing new ideas.Methods1. Establishment of chronic intermittent hypoxia and chronic continuous hypoxia rat model:26 healthy male SD rats, the SD rats were randomly divided into 3 groups, namely the control group (CG) 5,3 weeks of chronic intermittent hypoxia group (CIH group) 15,3 weeks chronic continuous hypoxia groups (CCH group) 6. All SD rats were in the normal diet, regular feeding of water to keep a week to adapt to new environments, CIH group of SD rats were placed in each 9AM-4PM intermittent hypoxia cabin pressure, to charge into the nitrogen cycle and air, each cycle of 30 seconds, filled with nitrogen, the minimum oxygen concentration of 6%-8%, duration of 20-25 seconds, then breathe the same time as the exclusion of air oxygen gas, so that the oxygen concentration gradually recovered to 21%, each loop time is 180 seconds, the cabin oxygen concentration fluctuations in intermittent hypoxia in 6%-21%, so for 3 weeks; CCH group of SD rats were placed daily 9AM-4PM chronic continuous hypoxia cabin pressure, nitrogen filled to continue, a chronic continuous hypoxic chamber 12% oxygen concentration, so for 3 weeks; CG of SD rats were not any treatment, experimental period of 3 weeks.2. Laboratory testing:Conventional SD end of the experiment rats were sacrificed, heart blood 5ml, send the Second Xiangya Hospital, Central South University laboratory, automatic biochemical analyzer of serum triglyceride (TG), total cholesterol (CHOL), low density lipoprotein cholesterol (LDL); by enzyme-linked immunosorbent assay of serum NF-κB, IL-6, HIF-1a, ox-LDL concentrations.Results1.3 weeks of intermittent hypoxia group compared with the control group body weight increased significantly (P<0.05); continuous hypoxia for 3 weeks compared with the control group body weight increased significantly (P<0.05); intermittent hypoxia for 3 weeks group and continuous hypoxia for 3 weeks significantly increased body weight compared (P<0.05).2.3 weeks of intermittent hypoxia group compared with the control group blood pressure was significantly higher (P<0.05); continuous hypoxia for 3 weeks compared with the control group blood pressure was significantly higher (P<0.05); intermittent hypoxia for 3 weeks group and continuous hypoxia for 3 weeks significantly increased blood pressure compared with high (P<0.05).3.3 weeks of intermittent hypoxia group and hypoxia for 3 weeks continuous group than the control group compared to NF-κB, IL-6, LDL, ox-LDL were significantly increased (P<0.01); intermittent hypoxia for 3 weeks group and continuous hypoxia for 3 weeks compared NF-κB, IL-6, LDL, ox-LDL were significantly increased (P<0.05); and TG, CHOL, HIF-1a in each group showed no significant difference.4. This study NF-κB, IL-6, LDL, ox-LDL 22 comparisons between the positive correlation:NF-κB and IL-6 compared positively correlated (r= 0.759, P<0.01); NF-κB and LDL Comparison of positive correlation (r= 0.839, P<0.01); NF-κB and ox-LDL compared positively correlated (r= 0.720, P<0.01); IL-6 and LDL compared positively correlated (r= 0.875, P<0.01); IL-6 compared with ox-LDL was positively correlated (r= 0.795, P<0.01); LDL compared with ox-LDL was positively correlated (r= 0.809, P<0.01).Conclusion1. Chronic intermittent hypoxia and chronic continuous hypoxia can lead to abnormal LDL, ox-LDL lipid metabolism in rats, which is correlated with the activation of NF-κB and the increased content of IL-6.2. Chronic intermittent hypoxia and chronic continuous hypoxia compared with the former NF-κB,IL-6,LDL,ox-LDL and blood pressure,body weight impact is more obvious than the latter.