Department of Kinesiology and Integrative Physiology, Michigan Technological University, Houghton, Michigan.
Am J Physiol Heart Circ Physiol. 2021 Jan 1;320(1):H248-H255. doi: 10.1152/ajpheart.00448.2020. Epub 2020 Nov 8.
Electronic cigarettes (e-cigarettes) are marketed as an alternative to smoking for those who want to decrease the health risks of tobacco. Tobacco cigarettes increase heart rate (HR) and arterial pressure, while reducing muscle sympathetic nerve activity (MSNA) through sympathetic baroreflex inhibition. The acute effects of e-cigarettes on arterial pressure and MSNA have not been reported: our purpose was to clarify this issue. Using a randomized crossover design, participants inhaled on a JUUL e-cigarette containing nicotine (59 mg/mL) and a similar placebo e-cigarette (0 mg/mL). Experiments were separated by ∼1 mo. We recorded baseline ECG, finger arterial pressure ( = 15), and MSNA ( = 10). Subjects rested for 10 min (BASE) and then inhaled once every 30 s on an e-cigarette that contained nicotine or placebo (VAPE) for 10 min followed by a 10-min recovery (REC). Data were expressed as Δ means ± SE from BASE. Heart rate increased in the nicotine condition during VAPE and returned to BASE values in REC (5.0 ± 1.3 beats/min nicotine vs. 0.1 ± 0.8 beats/min placebo, during VAPE; < 0.01). Mean arterial pressure increased in the nicotine condition during VAPE and remained elevated during REC (6.5 ± 1.6 mmHg nicotine vs. 2.6 ± 1 mmHg placebo, during VAPE and 4.6.0 ± 1.7 mmHg nicotine vs. 1.4 ± 1.4 mmHg placebo, during REC; < 0.05). MSNA decreased from BASE to VAPE and did not restore during REC (-7.1 ± 1.6 bursts/min nicotine vs. 2.6 ± 2 bursts/min placebo, during VAPE and -5.8 ± 1.7 bursts/min nicotine vs. 0.5 ± 1.4 bursts/min placebo, during REC; < 0.05). Our results show that acute e-cigarette usage increases mean arterial pressure leading to a baroreflex-mediated inhibition of MSNA. The JUUL e-cigarette is the most popular e-cigarette in the market. In the present study, inhaling on a JUUL e-cigarette increased mean arterial pressure and heart rate, and decreased muscle sympathetic nerve activity (MSNA). In contrast, inhaling on a placebo e-cigarette without nicotine elicited no sympathomimetic effects. Although previous tobacco cigarette studies have demonstrated increased mean arterial pressure and MSNA inhibition, ours is the first study to report similar responses while inhaling on an e-cigarette. Listen to this article's corresponding podcast at @ https://ajpheart.podbean.com/e/aerosolized-nicotine-and-cardiovascular-control/.
电子香烟(电子烟)作为一种降低吸烟危害的替代品,正被推向市场。烟草香烟通过交感神经反射抑制增加心率(HR)和动脉压,同时降低肌肉交感神经活动(MSNA)。电子烟对动脉压和 MSNA 的急性影响尚未报道:我们的目的是澄清这个问题。采用随机交叉设计,参与者吸入含有尼古丁(59mg/ml)的 JUUL 电子烟和类似的安慰剂电子烟(0mg/ml)。实验间隔约 1 个月。我们记录了基线心电图、手指动脉压(=15)和 MSNA(=10)。受试者休息 10 分钟(BASE),然后每隔 30 秒吸入一次含有尼古丁或安慰剂的电子烟(VAPE),持续 10 分钟,然后恢复 10 分钟(REC)。数据表示为从 BASE 的 Δ平均值±SE。在 VAPE 期间,尼古丁状态下的心率增加,在 REC 期间恢复到 BASE 值(5.0±1.3 次/分钟尼古丁与 0.1±0.8 次/分钟安慰剂,在 VAPE 期间;<0.01)。在 VAPE 期间,尼古丁状态下的平均动脉压升高,在 REC 期间仍保持升高(6.5±1.6mmHg 尼古丁与 2.6±1mmHg 安慰剂,在 VAPE 期间;4.6.0±1.7mmHg 尼古丁与 1.4±1.4mmHg 安慰剂,在 REC 期间;<0.05)。MSNA 在从 BASE 到 VAPE 的过程中下降,在 REC 期间没有恢复(7.1±1.6 次/分钟尼古丁与 2.6±2 次/分钟安慰剂,在 VAPE 期间;5.8±1.7 次/分钟尼古丁与 0.5±1.4 次/分钟安慰剂,在 REC 期间;<0.05)。我们的结果表明,急性电子烟使用会增加平均动脉压,导致压力反射介导的 MSNA 抑制。JUUL 电子烟是市场上最受欢迎的电子烟。在本研究中,吸 JUUL 电子烟会增加平均动脉压和心率,并降低肌肉交感神经活动(MSNA)。相比之下,吸不含尼古丁的安慰剂电子烟不会引起交感神经兴奋作用。尽管之前的烟草香烟研究表明平均动脉压升高和 MSNA 抑制,但我们的研究是第一个报告在吸电子烟时出现类似反应的研究。请在 @https://ajpheart.podbean.com/e/aerosolized-nicotine-and-cardiovascular-control/ 收听本文的相应播客。