Department of Emergency Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Toxicol Lett. 2010 Feb 15;192(3):349-55. doi: 10.1016/j.toxlet.2009.11.008. Epub 2009 Nov 12.
Epidemiological studies show an association between particulate matter exposure and acute heart failure. However, underlying mechanisms remain unclear. In this study, we investigated acute cardiac hemodynamic effects and related mechanisms after 1 day exposure to diesel exhaust particles (DEPs). Male Sprague-Dawley rats were randomized and instilled with 250 microg (low dose) or 500 microg (high dose) of DEP or saline placebo intra-tracheally. The cardiac systolic function by dP/dt(40) and diastolic functions by maximal negative dP/dt were both worse in DEP low dose and DEP high dose groups than the control group, respectively. In the heart rate variability analysis, SDNN in DEP low dose and DEP high dose groups were both lower than the control group. The low frequency heart rate variability was higher in the DEP groups compared to the control group. The cardiac IL-1beta expression and circulating cardiac troponin I level were higher in the DEP group than the control group. Plasma IL-1beta and IL-6 protein were significantly higher in the DEP groups than the control group. In conclusion, DEP exposure causes acute cardiac systolic and diastolic dysfunction. The changes may be related to decreased heart rate variability, increased cardiac inflammatory reaction and myocardial damage.
流行病学研究表明，颗粒物暴露与急性心力衰竭之间存在关联。然而，其潜在机制尚不清楚。在这项研究中，我们研究了暴露于柴油机排气颗粒物（DEP）1 天后对急性心脏血流动力学的影响及其相关机制。雄性 Sprague-Dawley 大鼠随机接受气管内滴注 250μg（低剂量）或 500μg（高剂量）DEP 或生理盐水安慰剂。与对照组相比，DEP 低剂量组和 DEP 高剂量组的心脏收缩功能 dP/dt(40)和舒张功能最大负 dP/dt 均较差。在心率变异性分析中，DEP 低剂量组和 DEP 高剂量组的 SDNN 均低于对照组。与对照组相比，DEP 组的低频心率变异性更高。DEP 组的心脏白细胞介素-1β表达和循环心肌肌钙蛋白 I 水平均高于对照组。DEP 组的血浆白细胞介素-1β和白细胞介素-6 蛋白明显高于对照组。总之，DEP 暴露会导致急性心收缩和舒张功能障碍。这些变化可能与心率变异性降低、心脏炎症反应增强和心肌损伤有关。
