Ambient particulate matter induces relaxation of rat aortic rings in vitro
Ambient particulate matter induces relaxation of rat aortic rings in vitro
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DOI：
10.1191/096032701678227677
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发表时间：
2001-05-01
影响因子：
2.8
通讯作者：
Borm, PJA
中科院分区：
文献类型：
--
作者：
Knaapen, AM;den Hartog, GJ;Borm, PJA
流行病学研究表明，颗粒物（PM）的环境水平与心血管疾病死亡率增加之间存在关联。然而，其内在机制尚不清楚。我们假设PM在吸入后移位，可能影响血管平滑肌功能。因此，对总悬浮颗粒物（TSP）进行采样，并研究其影响主动脉肌收缩的能力。TSP和TSP上清液（TSP-sup）均能浓度依赖性地舒张苯肾上腺素（PE）预收缩的主动脉环。300 μ g/ml TSP诱导的舒张占总收缩的51.5 ± 3.1%。在60和100 μ g/ml时，TSP诱导的舒张显著高于TSP-sup。超细二氧化钛，作为一个模型来研究超细颗粒的作用，没有表现出效果。可溶性铁，目前在TSP悬浮液，似乎不参与，螯合与去铁胺没有影响TSP诱导的松弛。然而，TSP的影响被抑制Trolox，这表明氧化剂的作用。裸胸主动脉环表明，TSP的影响只有部分内皮依赖性，而预孵育L-NAME增加TSP诱导的舒张。从这些数据中，我们得出结论，颗粒核心和可溶性成分的TSP可以影响平滑肌功能，导致血管收缩反应的变化。
Epidemiological studies have shown an association between ambient levels of particulate matter (PM) and increased mortality from cardiovascular diseases. However, the underlying mechanisms are still not clear. We hypothesised that PM, when translocated after inhalation, could affect vascular smooth muscle function. Therefore, total suspended particulate matter (TSP) was sampled and investigated for its ability to affect aortic muscle contraction. Both TSP and TSP supernatant (TSP-sup) induced a concentration-dependent relaxation of phenylephrine (PE)-precontracted aortic rings. Relaxation induced by 300 mug/ml TSP was 51.5 +/- 3.1% of total contraction. At 60 and 100 mug/ml, relaxation induced by TSP was significantly higher compared to TSP-sup. Ultrafine TiO2, used as a model to investigate the role of ultrafine particles, did not show an effect. Soluble iron, present in TSP suspensions, seems not to be involved, as chelating with deferoxamine did not affect TSP-induced relaxation. However, TSP effects were inhibited by Trolox, suggesting a role of oxidants. Nudation of aortic rings showed that effects of TSP were only partly endothelium-dependent, while preincubation with L-NAME increased TSP-induced relaxation. From these data, we conclude that both the particle core and soluble components of TSP can affect the smooth muscle function, leading to changes in the vascular contractile response.