脓毒症心肌病对大鼠心室肌细胞的损伤及维生素C的干预效果

The injury of ventricular myocytes in rats with septic cardiomyopathy and the intervention effect of vitamin C

目的:研究脓毒症对大鼠心肌的损伤及维生素C的干预效果。方法:选取90只SD雄性大鼠随机分成三组,将其中两组进行脓毒症造模,一组予维生素C干预(A组)、另一组作为脓毒症组(B组)及第三组为对照组(C组),造模成功后24 h和48 h检测降钙素原(procalcitonin,PCT)、脂多糖(lipopolysaccharide,LPS)及超氧化物歧化酶(superoxide dismutase,SOD)水平;造模后24 h检测大鼠左室射血分数以及左心室收缩末期和舒张末期容积和心肌细胞动作电位及离子通道电压与密度变化。结果:A组及B组PCT、LPS均升高且高于C组,而B组在造模后48 h的PCT及LPS高于A组。超声提示A、B两组大鼠左室射血分数、收缩及舒张末期容积均降低,但B组更为显著;与C组相比,A、B两组的心肌细胞动作电位显著延长、而B组延长更为明显;与C组相比,A组与B组的I_(Ca-L)和I_(to)密度明显降低、B组更为显著(均P<0.05);造模后48 h SOD检测发现A组较C组相比升高、B组与C组比较降低(均P<0.05)。结论:脓毒症大鼠PCT、LPS升高,维生素C干预可以降低其水平;脓毒症大鼠SOD降低,维生素C干预可以减轻SOD降低水平。脓毒症大鼠心脏功能下降,且心肌细胞动作电位明显延长,同时脓毒症大鼠I Ca-L和I to密度降低,而进行维生素C干预后均可改善。

Objective:To study the effect of sepsis on myocardial injury and the intervention effect of vitamin C in rats.Methods:Ninety SD male rats were randomly divided into three groups.One group was treated with vitamin C(group A),the other group was treated with vitamin C as sepsis group(group B)and the last group was control group(group C).The levels of procalcitonin(PCT),lipopolysaccharide(LPS)and superoxide dismutase(SOD)were detected at 24 h and 48 h after successful modeling.The changes of left ventricular ejection fraction,left ventricular end-systolic and end-diastolic volume,myocardial cell action potential and ion channel voltage and density were detected 24 hours after modeling.Results:The levels of PCT and LPS in group A and group B were higher than those in group C,while the levels of PCT and LPS in group B were higher than those in group A at 48 h after modeling.Ultrasound showed that the left ventricular ejection fraction,systolic and end-diastolic volume of rats in group A and group B decreased,but group B was more significant.Compared with group C,the action potential of myocardial cells in group A and group B was significantly prolonged,while that in group B was more obvious.Compared with group C,the density of I_(Ca-L)and I_(to)in group A and group B was significantly lower than that in group C,and that in group B was more significant(all P<0.05).At 48 hours after modeling,SOD detection showed that group A was higher than group C,and group B was lower than group C(all P<0.05).Conclusion:PCT and LPS increased in septic rats,and vitamin C intervention can reduce their levels;SOD decreased in septic rats,and vitamin C intervention could reduce the level of SOD.The cardiac function of septic rats decreased,and the action potential of myocardial cells was significantly prolonged.At the same time,the density ofI Ca-L and I to in septic rats decreased,which could be improved after vitamin C intervention.