Influence of Nicotine from Diverse Delivery Tools on the Autonomic Nervous and Hormonal Systems

Figure 1. CO dynamics in the exhalation of a volunteer after smoking two nicotine-free cigarettes with an interval of 90 min.

Figure 2. Increase in parasympathetic activity in a volunteer when smoking two nicotine-free cigarettes (central points on the graph) with an interval of 90 min but not imitating smoking (Imit) in comparison with the pre-smoking and post-smoking stages.

Figure 3. Dynamics of the RR intervals of a volunteer at different stages of testing a nicotine-free cigarette. To accurately determine the correspondence of the time coordinates of each stage of the experiment in the figure, the test protocol should be used. Green color—imitation of smoking, blue color—1st cigarette zone, red color—2nd cigarette zone. (Table S1, Supplementary Materials).

Figure 4. The dynamics of the total power spectrum (TP) during the testing of nicotine-free cigarettes.

Figure 5. Dynamics of HRV indicators in a volunteer during the testing period for nicotine-free cigarettes.

Figure 6. Influence of the smoke extract of the nicotine-free cigarette tar, free of the gas-phase components, on HRV in four non-smoking volunteers. PG0 refers to 25 puffs of the electronic cigarette with propylene glycol (control), and PGE pertains to 25 puffs of the electronic cigarette with the smoke extract, while NFC denotes 10 puffs of a Nirdosh nicotine-free cigarette. Designations of statistically significant differences (p < 0.05): a—relative to the baseline in the experiment with smoking (t = 0 h), b—in the experiment with smoking relative to the electronic cigarette with propylene glycol (PG0), c—in the experiment with smoking relative to the electronic cigarette with the cigarette-smoke tar extract (PGE), d—in the experiment with the electronic cigarette with the cigarette-smoke tar extract relative to the baseline (t = 0 h), e—in the experiment with the electronic cigarette with the tar extract (PGE) relative to the electronic cigarette with propylene glycol (PG0).

Figure 7. HRV dynamics (percentage of adjacent RR intervals differing by more than 50 ms) after the use of different nicotine-containing products by a smoking volunteer. Electronic cigarette with a nicotine-free filler (100% propylene glycol) was used as a control. The subject took 8 puffs in 3.5 min for all smoking simulators, including cigarettes, and also used a nicotine pack for 40 min.

Figure 8. Dynamics of RR intervals after the use of various nicotine-containing products by a smoking volunteer.

Figure 9. Dynamics of the RMSSD indicator during the period using ANDS by a smoker, including 5 min before the smoking session, the smoking session itself and immediately after its end (usually less than 1 min).

Figure 10. The maximum changes in the level of cortisol (relative to the baseline) in the saliva of a volunteer after testing different types of nicotine and nicotine-free products and the imitation of smoking. Experimental data acquired with oral nicotine products (packs with a nicotine content of 0.4 and 6 mg) are given in blue, while the data obtained for products with an inhalation mod for the nicotine delivery are marked in red (CC refers to a conventional cigarette with nicotine 0.4 mg, glo denotes the gloTM tobacco heating system and a nicotine-free cigarette is designated as Smoke_0, while SmImit is for the imitation of smoking with an unlit cigarette). Data are presented as means of three measurements with the standard deviation. All experiments were carried out at the same time of the day with an interval of 2 to 3 days between tests. The experiment involved a volunteer from the group of rare smokers (2–4 cigarettes per week with a nicotine content of 0.4 mg).

Figure 11. Dynamics of cotinine in saliva (red straight line with triangles) and the LF/HF ratio (black line with circles) during the period of nic-pack testing (4 packs with 4 mg of nicotine). Periods of fixation of packs in the oral cavity are marked with blue-shaded areas.

Figure 12. Dynamics of nicotine in saliva (collection of saliva every 45 min immediately before using the next pack). Regression line (red) p = 0.0018. 95% confidence level (green dots).