GaAs半导体激光照射足三里穴对人体痛阈的影响

Effect of GaAs Semiconductor Laser Irradiation of Zusanli Acupoints on Pain Threshold in Healthy Subjects

目的 探讨GaAs 半导体激光穴位照射对人体的镇痛效应。方法 健康受试者30 名分为3 组,每组10 名。(1) 组采用GaAs 半导体激光照射双侧足三里穴(GaAs 组) ,光斑直径0-2 cm ,脉冲频率95 Hz,平均功率密度159 m W/cm2 ,每侧穴位照射15 min 。(2) 组以激光和低频电脉冲(LFEP) 交替作用于双侧足三里穴(GaAs + LFEP 组) ,每侧穴位激光和LFEP各作用15 min ,激光参数同GaAs 组,LFEP 取可调锯齿状波,频率10 Hz,刺激强度以受试者能耐受为限。(3) 组为对照组,仅将激光照射头放置于双侧足三里穴上15 min ,但无激光输出。于照射足三里穴前及照射后15 、30 min ,采用钾离子透入测痛法,分别测量受试者腹部和耳垂痛阈,观察照射前后痛阈变化,并进行组间比较。结果 GaAS组穴位照射后15 和30 min ,腹部痛阈分别比照射前提高35-6 % ( P< 0-05) 和39-7 % ( P< 0-01) ,耳垂痛阈分别比照射前提高26-7 % ( P< 0-05) 和24-4 % ( P> 0-05) ;GaAs + LFEP 组刺激穴位后15 和30 min ,腹部痛阈分别提高42-3 % ( P<0-05) 和44-9 % ( P< 0-05) ,耳垂痛阈均提高44-6 % ( P< 0-05) 。GaAs 组和GaAs+ LFEP 组照射或刺激穴位后不同时间的痛阈变化分别与对照组比较,腹部痛阈增高幅度差异均有显著意义( P< 0-05) ;耳垂痛阈增高幅度GaAs 组差?

Objective The analgesic effect of semiconductor GaAs laser acupoints irradiation and its machanism of action wese investigated in healthy subjects. Methods 30 healthy subjects were equally divided into three groups: the GaAs laser acupoints irradiation group, the GaAs laser acupoints irradiation alternatively combined with low frequency electropulse stimulation group and the control group with laser probe merdy placed on the acupoints for 15 min without any irradiation. All laser irradiations on bilateral acupoints lasted for 15 min with a light spot diameter of 0 2 cm, pulse frequency of 95 Hz and mean power density of 159 mW/cm 2. The electropulse was induced by using an adjustable saw tooth wave generator with a frequency of 10 Hz. The pain thresholds were tested by potassium ion density dolorimeter before, 15 and 30 minutes after GaAs laser irradiation or alternatively combined with low frequency electropulse stimulation on bilateral Zusanli(v36) acupoints for 15 minutes. Changes in pain thresholds of the abdomen and the ear lobe were recorded in the experimental groups, and were compared with those of the control group. Results The pain thresholds of the abdomen and ear lobe were elevated in both experimental groups 15 and 30 minutes after treatment. The elevated amplitudes of the pain thresholds of the abdomen were 35 6%(P<0 05) and 39 7% respectively (P<0 01) in the GaAs laser group, 42 3%(P<0 05) and 44 9(P<0 05) respectively in the GaAs laser alternalively combined with low frequency electropulse stimulation group. The elevated amplitudes of pain thresholds of the ear lobe were 26.7%(P<0 05) and 24 4%(P>0 05) respectively in the GaAs laser group, both 44 6%(P<0 05) in the GaAs laser alternatively combined with low frequency electropulse stimulation group. Changes in pain threvholds of diffeuent time interval after treatment in both experimental groups were compared with those of the control group: all differences of the pain thresholds of the abdomen were significant(P<0 05), the differences of the pain thresholds of the ear lobe were not significant(P>0 05) in the GaAs laser group, but the differences were significant(P<0 05) in the GaAs laser alternatively combined with low frequency electropulse stimulation group. Conclusions It is suggested that GaAs laser irradiation on Zusanli(v36) acupoints may exert obvious analgesic effect, and if combined with low frequency electropulse stimulation it may further enhance the analgesic effect of the GaAs laser irradiation. Moreover, the combined treatment with both laser and low frequency electropulse has a prolonged and general analgesic effect.