Cardiovascular Research Institute, University of California, San Francisco, San Francisco, California, USA.
Division of Clinical Pharmacology and Experimental Therapeutics, University of California, San Francisco, San Francisco, California, USA.
Tob Control. 2018 Nov;27(Suppl 1):s13-s19. doi: 10.1136/tobaccocontrol-2018-054325. Epub 2018 Sep 11.
Heated tobacco products (also called 'heat-not-burn' products) heat tobacco at temperatures below that of combustion, causing nicotine and other compounds to aerosolise. One such product, IQOS from Philip Morris International, is being marketed internationally with claims of harm reduction. We sought to determine whether exposure to IQOS aerosol impairs arterial flow-mediated dilation (FMD), a measure of vascular endothelial function that is impaired by tobacco smoke.
We exposed anaesthetised rats (n=8/group) via nose cone to IQOS aerosol from single HeatSticks, mainstream smoke from single Marlboro Red cigarettes or clean air for a series of consecutive 30 s cycles over 1.5-5 min. Each cycle consisted of 15 or 5 s of exposure followed by removal from the nose cone. We measured pre-exposure and postexposure FMD, and postexposure serum nicotine and cotinine.
FMD was impaired comparably by ten 15 s exposures and ten 5 s exposures to IQOS aerosol and to cigarette smoke, but not by clean air. Serum nicotine levels were similar to plasma levels after humans have smoked one cigarette, confirming that exposure conditions had real-world relevance. Postexposure nicotine levels were ~4.5-fold higher in rats exposed to IQOS than to cigarettes, despite nicotine being measured in the IQOS aerosol at ~63% the amount measured in smoke. When IQOS exposure was briefer, leading to comparable serum nicotine levels to the cigarette group, FMD was still comparably impaired.
Acute exposures to IQOS aerosol impairs FMD in rats. IQOS use does not necessarily avoid the adverse cardiovascular effects of smoking cigarettes.
加热型烟草制品（也称为“加热不燃烧”产品）在低于燃烧温度的温度下加热烟草，导致尼古丁和其他化合物气溶胶化。菲利普莫里斯国际公司（Philip Morris International）生产的 IQOS 就是这样一种产品，它在国际上销售，并声称具有减少危害的作用。我们试图确定接触 IQOS 气溶胶是否会损害血管内皮功能的动脉血流介导扩张（FMD），而烟草烟雾会损害这种功能。
我们通过鼻锥让麻醉大鼠（每组 8 只）连续暴露于 IQOS 气溶胶、单支万宝路红香烟主流烟雾或清洁空气中，每个循环持续 1.5-5 分钟，每个循环包括 15 或 5 秒的暴露时间和 5 秒的移除时间。我们测量了暴露前和暴露后的 FMD，以及暴露后的血清尼古丁和可替宁。
10 次 15 秒和 10 次 5 秒的 IQOS 气溶胶暴露和香烟烟雾暴露同样损害了 FMD，但清洁空气暴露没有。暴露后大鼠血清尼古丁水平与人类吸完一支香烟后的血浆尼古丁水平相似，这证实了暴露条件与实际情况相关。尽管 IQOS 气溶胶中的尼古丁含量约为烟雾中的 63%，但与香烟相比，暴露于 IQOS 的大鼠血清中的尼古丁水平仍高出约 4.5 倍。当 IQOS 暴露时间更短时，导致与香烟组相似的血清尼古丁水平时，FMD 仍受到类似程度的损害。
急性暴露于 IQOS 气溶胶会损害大鼠的 FMD。使用 IQOS 并不一定能避免吸烟带来的心血管不良影响。
