模拟月尘对大鼠心率变异性及系统炎症的影响

Effects of Lunar Dust Simulant on Heart Rate Variability and Systemic Inflammation of Rats

目的探讨模拟月尘(lunar dust simulant,LDS)对大鼠心率变异性(heart rate variability,HRV)及系统炎症损伤的影响。方法24只大鼠随机分为对照组(Con),LDS低(0.35mg/只大鼠)、中(1.05mg/只大鼠)、高(3.15mg/只大鼠)3个剂量组,通过气管滴注染毒法建立模拟月尘损伤模型。记录大鼠心率和心率变异性(heart rate variability,HRV)变化,并观察大鼠心脏结构病理变化和血清中炎症因子变化。利用qPCR和Western blot法检测大鼠心脏组织中内皮型一氧化氮合酶(endothelial nitric oxide synthase,eNOS)、诱导型一氧化氮合酶(inducible nitric oxide synthase,iNOS)和细胞间黏附分子-1(intercellular cell adhesion molecule-1,ICAM-1)基因和蛋白表达水平。结果与对照组相比,在中、高剂量暴露组中心率明显降低,HRV明显改变(P<0.05,P<0.01)。HE染色显示心脏病理特征随LDS剂量的增加而增强,血清检测结果表明系统炎症因子水平增加(P<0.05,P<0.01)。LDS3个剂量暴露组心脏组织iNOS表达明显上调,中、高剂量组ICAM-1表达明显上调(P<0.05,P<0.01)。结论 LDS暴露导致系统炎性病变,影响自主神经功能。同时,LDS可激活血管内皮细胞,损害内皮功能,具有导致心血管疾病的潜在风险。

Objective To investigate the effects of lunar dust simulant(LDS)on heart rate variability(HRV)and systemic inflammatory lesions.Methods Twenty-four rats were randomly divided into control group,LDS low dose group(0.35 mg per rat),LDS middle dose group(1.05 mg per rat)and LDS high dose group(3.15 mg per rat).LDS damage rat models were established by intratracheal instillation of LDS suspension.Heart rate(HR)and heart rate variability(HRV)changes of rats were recorded and HE staining was used to observe the ultrastructure of rat hearts.The levels of inflammatory factors in serum were detected.qPCR and Western blot were used to detect the expression of endothelial nitric oxide synthase(eNOS),inducible nitric oxide synthase(iNOS)and intercellular cell adhesion molecule-1(ICAM-1)in heart tissues of rats.Results Compared with the control group,the HR was significantly decreased and the HRV was significantly changed in the middle and high dose groups(P<0.05,P<0.01).HE staining showed that the pathological features of the hearts increased with the dose of LDS,the levels of systemic inflammatory factors increased(P<0.05,P<0.01).In the heart tissues,the expression of iNOS was significantly up-regulated in LDS exposed groups,and ICAM-1 was significantly up-regulated in middle and high dose groups(P<0.05,P<0.01).Conclusion LDS leads to systemic inflammatory lesions and affects autonomic function.Furthermore,LDS can activate vascular endothelial cells,impair endothelial function leading to potential risk of cardiovascular disease.