Joukar S, Sheibani M
Physiology Research Center, Institute of Basic and Clinical Physiology Sciences, Kerman University of Medical Sciences, Kerman, Iran.
Cardiovascular Research Center, Institute of Basic and Clinical Physiology Sciences, Kerman University of Medical Science, Kerman, Iran.
Auton Autacoid Pharmacol. 2017 Jun;37(3):44-48. doi: 10.1111/aap.12059.
The effect of nicotine on heart rate variability (HRV) is controversial. Autonomic nervous system is the main regulator of heart rhythm, and heart rate variability is an appropriate index to assessment of the effects of the autonomic system on heart. In this study, the combination effect of nicotine and black tea consumption on sympatho-vagal balance and heart rate variability was investigated in rats. Male Wistar rats were randomized into four groups as control, tea (2.5 g/100 cc, daily), nicotine (2 mg/kg/d) and tea plus nicotine groups which treated for 28 days, and in the 29th day, their electrocardiograms (lead II) were recorded. The mean of high-frequency power (HF) in tea, nicotine and tea plus nicotine groups was significantly more than control group (P < .05), and low-frequency power/high-frequency power (LF/HF) ratio in the nicotine and tea + nicotine groups was significantly less than control group (P < .05). LF values did not differ significantly among groups. Mean of standard deviation of normal RR intervals (SDNN) and square root of the mean squared differences of successive RR intervals (RMSSD) increased significantly in tea, nicotine and tea + nicotine groups in comparison with control group (P < .05) Overall, 4-week administration of black tea, nicotine or their combination with dosages used in this study can increase the heart rate variability and improve the sympatho-vagal balance in rat.
尼古丁对心率变异性（HRV）的影响存在争议。自主神经系统是心律的主要调节者，而心率变异性是评估自主系统对心脏影响的合适指标。在本研究中，研究了尼古丁与饮用红茶对大鼠交感 - 迷走神经平衡和心率变异性的联合作用。雄性Wistar大鼠被随机分为四组，即对照组、茶组（2.5 g/100 cc，每日）、尼古丁组（2 mg/kg/d）和茶加尼古丁组，进行为期28天的处理，并在第29天记录其心电图（II导联）。茶组、尼古丁组和茶加尼古丁组的高频功率（HF）均值显著高于对照组（P <.05），尼古丁组和茶加尼古丁组的低频功率/高频功率（LF/HF）比值显著低于对照组（P <.05）。各组间低频值无显著差异。与对照组相比，茶组、尼古丁组和茶加尼古丁组的正常RR间期标准差（SDNN）均值和连续RR间期平方差的平方根（RMSSD）显著增加（P <.05）。总体而言，本研究中使用的剂量的红茶、尼古丁或它们的组合进行4周给药可增加大鼠的心率变异性并改善交感 - 迷走神经平衡。
