Effects of midazolam and flumazenilon autonomic nervous activities

通过心率、皮肤血流量和血压波动的功率谱分析，研究咪达唑仑和氟马西尼对自主神经活动抑制的影响。健康男性志愿者参加两次不同的训练，M组仅注射咪达唑仑0.07 mg/kg，MFmz组在注射相同剂量的咪达唑仑18分钟后注射氟马西尼0.3 mg。用SRR-5(GMS公司)记录RR间期，用AFL2激光多普勒血流仪(Advance公司)测量手背血流量。连续的模拟数据通过A/D转换器输入计算机PC-9801BA2(NEC公司)，并将数据分成60秒的子序列。用Jentow 7700(Nihon-Khorin Co.)并用自主神经系统软件包(Nihon-Khorin Co.)进行分析。使用MemCalc系统(Suwa Trust Co.)进行最大熵法分析。RR间期和血压的功率谱密度分为4个分量(0.04~0.4 Hz)，血流功率谱密度分为6个分量(0.04~2.2 Hz)，RR间期0.04~0.4 Hz功率在5min时降至基线的27~50%(平均值)。在MFmz组，20min时功率下降到127-150%。血流量：两组在5min时0.1~0.20赫兹功率均降至基线的26~77%。在MFmz组，这两个值在20min时均升高。在眼压测量血压中也观察到同样的趋势，表明咪达唑仑主要抑制低频功率，这意味着它对交感神经活动的抑制比对副交感神经活动的抑制更大，而氟马西尼则拮抗这种抑制作用。

The effect of midazolam and flumazenil on depression of autonomic nervous activities were studied using power spectral analysis of fluctuations in heart rate, cutaneous blood flow and tonometry blood pressure.Healthy young male volunteers participated in two different sessions ; Group M received 0.07 mg/kg of midazolam only, and in Group MFmz, flumazenil 0.3 mg was administered 18 min after the injection of the same dose of midazolam. RR interval was recorded with SRR-5 (GMS Co.), and blood flow at the dorsum manus was measured with a laser doppler flowmeter AFL2 (Advance Co.). The successive analogue data were inputted via an A/D converter into a computer PC-9801BA2 (NEC Co.), and data were divided into subseries of 60 sec. Tonometry blood pressure were recorded with Jentow 7700 (Nihon-Khorin Co.) and analyzed by Autonomic Nervous System Package (Nihon-Khorin Co.). Analysis was carried out by the maximum entropy method (MEM) using MemCalc system (Suwa Trust Co.). Power spectrum densities were separated into four components (0.04-0.4Hz) in RR intervals and tonometry blood pressure, and into six (0.04-2.2Hz) in blood flow.The powers of 0.04-0.4Hz in RR intervals decreased to 27-50% (mean) of the basline value at 5 min in both groups. In Group MFmz, the decreased powers increased to 127-150% at 20 min. As to blood flow, powers of 0.1-0.20Hz decreased to 26-77% of the basline value at 5 min in both groups. In Group MFmz both values increased at 20 min. The same trend was obsewrved in tonometry blood pressure.It is indicated that midazolam depresses mainly the powers of low frequency, which means it depresses sympathetic nervous activity more than parasympathetic activity, and flumazenil antagonizes the depression.