Little C J, Julu P O, Hansen S, Reid S W
Department of Veterinary Clinical Studies, University of Glasgow Veterinary School, Bearsden, Glasgow G61 1QH, United Kingdom.
Am J Physiol. 1999 Feb;276(2):H758-65. doi: 10.1152/ajpheart.1999.276.2.H758.
Rapid changes in heart rate are caused by changes in parasympathetic tone. The NeuroScope is an electronic device designed to offer an objective real-time measure of instantaneous cardiac vagal tone by phase demodulation of a high-resolution time domain of R-R wave intervals. Data are displayed against an arbitrary but linear scale, the cardiac index of parasympathetic activity (CIPA). To validate this method, 10 conscious healthy dogs were each given six incremental doses of atropine (0.01 mg/kg) to a total dose of 0.06 mg/kg or equal volumes of saline. A dose-response curve was constructed. At the maximum dose of atropine, CIPA values fell to 1. 3 +/- 0.7% (SD) of baseline, whereas R-R intervals fell to 51.5 +/- 11.5% of baseline, and standard deviation of the R-R wave interval fell to 10.6 +/- 6.5% of baseline. These findings show that the NeuroScope can provide a specific real-time index of cardiac vagal tone in dogs without need for recourse to atropine.
心率的快速变化是由副交感神经张力的变化引起的。NeuroScope是一种电子设备，旨在通过对R-R波间期的高分辨率时域进行相位解调，提供即时心脏迷走神经张力的客观实时测量。数据以任意但线性的尺度显示，即副交感神经活动的心脏指数（CIPA）。为了验证该方法，对10只清醒的健康犬每只给予六次递增剂量的阿托品（0.01mg/kg），总剂量为0.06mg/kg或等量的生理盐水。构建了剂量反应曲线。在阿托品的最大剂量时，CIPA值降至基线的1.3±0.7%（标准差），而R-R间期降至基线的51.5±11.5%，R-R波间期的标准差降至基线的10.6±6.5%。这些发现表明，NeuroScope无需使用阿托品即可提供犬心脏迷走神经张力的特定实时指标。
