Study on cardiovascular injury of anesthesia rat induced by chronic intermittent hypoxia / 局解手术学杂志

ABSTRACT

Objective To investigate the effect of chronic intermittent hypoxia(CIH)on the cardiovascular system in anesthetized rats. Methods A totally of 72 male SD rats were randomly divided into three groups(n=24),namely the ormoxia control group(control group), the normoxia anesthesia group(model group)and the chronic intermittent hypoxia group(CIH group).Rats of the control group breathe nor-mally.The model group was given intraperitoneal injection of 10%hydration with 0.3 mL/kg,and the CIH group was given chronic intermit-tent hypoxic stimulation with 8 h/d in addtion to the model group.The difference of ultrasonic echocardiography data,blood pressure,endothe-lin type-1,and endothelial nitric oxide synthase(eNOS)in rats of the three groups were compared.After 28 days,these rats were sacrificed to observe the changes of myocardial cell structure.Results In the control group,the myocardial morphology was normal,the cells arranged e-venly,and there was no swelling and inflammation.In the model group,the myocardial cells were evenly arranged without hypertrophy and in-flammatory changes.In the CIH group,the myocardial cells in the hypoxic group were not evenly arranged,and hypertrophy,swelling,deform-ation,hyperchromia,and obvious inflammatory changes of the myocardial tissue were observed.In the control group,myocardial cell nucleus and cytoplasm were uniformly arranged,and there was no obvious changes in the model group.On the contrary,myocardial cell morphology changed obviously in the CIH group,with the cell morphology and size of the inhomogeneity increased, and the color of the apoptosis cells changes from light to dark.The tail artery systolic pressure of rats in CIH group was significantly higher than that of the control group and the model group,and the LVEF of CIH group was significantly lower than that of the other two groups(P<0.05).Ultrasound detection value sug-gests that the LVID and left ventricular of rats in the CIH group were slightly larger,and the diastolic function was normal.The LVDs of the model group and the CIH group were both higher than that of the control group with statistically significant difference(P<0.05).The RBC, HCT,dp/dtmax,and -dp/dtmax in the CIH group were significantly higher than those of the control group and the model group(P<0.05). Serum levels of endothelin-1 in CIH group were significantly higher than that of control group and model group,while the summation of serum NO2-/NO3-and eNOS in CIH group were significantly lower than those of the control group and the model group(P<0.05).Conclusion Chronic intermittent hypoxia can cause cardiac dysfunction in anesthetized rats,which may lead to the imbalance of serum endothelin-1 and NO levels,leading to endothelial dysfunction and myocardial injury.