目的 研究铁皮石斛(Dendrobium officinale Kimura et Migo)的体外抗氧化活性及通过测量经络电压探索铁皮石斛的归经作用.方法 测定铁皮石斛汤剂的氧化还原电位值、pH值、总抗氧化能力.召集20名健康志愿者按随机数字表法分为2组,试验组(服用铁皮石斛汤剂,8g铁皮石斛粉冲泡于80 mL水中),对照组(饮用等量水),每组10名.服用药物前后进行人体经络电压的测量,选取12条经络上(肺经、肝经、脾经、肾经、胃经、心经、大肠经、胆经、心包经、三焦经、小肠经、膀胱经)的合穴和原穴作为经络电压的测量点,均以合穴为正极,原穴为负极,记录经络电压的变化.结果 通过pH的测定结果可以看出铁皮石斛呈现弱酸性.与蒸馏水比较,铁皮石斛氧化还原电位降低,抗氧化能力及总抗氧化能力升高(P＜0.01).在经络电压测定中,与对照组比较,试验组大肠经、胆经、心包经、三焦经、小肠经和膀胱经的电压升高,肺经、肝经、脾经、肾经、胃经和心经的电压则无显著变化.结论 铁皮石斛对可以显著增加大肠经、胆经、心包经、三焦经、小肠经和膀胱经所属的六腑经络的电压,对肺经、肝经、脾经、肾经、胃经和心经所属的五脏经络的电压则无显著作用.经络电压的变化规律与铁皮石斛的抗氧化性具有一定的关联.

超氧化物歧化酶(SOD)是生物体内产生的一种主要抗氧化酶,能够针对性清除呼吸代谢产生的超氧阴离子自由基.牛奶中自身含有SOD,SOD也被作为食品添加剂加入乳制品中,用于提高产品的抗氧化性,具有保健的作用.为了研究SOD强化奶片的抗氧化性,以及从对人体经络电压作用的角度研究其功能,对奶片(1.00 g奶粉)和SOD强化奶片(0.99 g奶粉+0.01 g 2.53×106 U/g SOD酶)分别进行氧化-还原电位(ORP)、DPPH自由基清除能力、SOD活力检测.召集20名健康志愿者,随机分为两组进行双盲试验,奶片组合服1片奶片,SOD强化奶片组则含服1片SOD强化奶片.实时记录志愿者左侧12条经络,并且在监测的第25 min开始含服,含服前、后一共记录85 min.实验结果显示,与奶片相比,SOD强化奶片的SOD活性和还原性(ORP值降低)显著增加,在质量浓度为1.250 mg/mL与1.562 mg/mL时,可增加对DPPH自由基的清除率,在3.125 mg/mL时则降低对DPPH自由基的清除率.经络电压监测结果显示:针对肺经和胆经经络电压,奶片没有影响,而SOD强化奶片有影响;针对大肠经、脾经、小肠经、膀胱经、三焦经和肝经经络电压,奶片有影响,SOD强化奶片的影响更强;针对胃经、心经、肾经和心包经经络电压,奶片和SOD强化奶片都有一定的影响,且作用相似.

Objectives:To investigate the effect on essential hypertension of the topical application of TAT-Cu,Zn-superoxide dismutase （TAT-SOD） at left acupoint Zusanli （ST 36）,and to observe whether the change of electrical potential difference （EPD） can be related to the change of blood pressure.Methods:Sixteen patients with essential hypertension and 16 healthy subjects were included in the study.EPD between the left acupoints of Yanglingquan （GB 34） and Qiuxu （GB 40） was firstly screened out for the EPD detection.An intracellular superoxide quenching enzyme,TAT-SOD,was topically applied to the acupoint ST 36 within an area of 1 cm~2 once a day,and the influence on EPD was investigated.The dosage applied to TAT-SOD group （n=8） was 0.2 m L of 3000 U/m L TAT-SOD cream prepared by adding purified TAT-SOD to a vehicle cream,while placebo group （n=8） used the vehicle cream instead.The left acupoints of Yanglingquan （GB 34）and Qiuxu （GB 40） were selected for EPD measurement after comparing EPD readings between 5 acupoints on each of all 12 meridians.Results:EPDs between the left acupoints of GB 34 and GB 40 for 16 patients of essential hypertension and 16 healthy subjects were 44.9±6.4 and 5.6±0.9 m V,respectively.Daily application of TAT-SOD for 15 days at ST 36 of essential hypertension patients significantly decreased systolic blood pressure （SBP） and diastolic blood pressure （DBP） of 179.6 and 81.5 mm Hg to 153.1 and 74.1 mm Hg,respectively.Responding to the change in blood pressure,EPD between the left acupoints of GB 34 and GB40 also declined from 44.4 to 22.8 m V with the same trend.No change was observed with SBP,DBP and EPD between the left acupoints of GB 34 and GB 40 with the daily application of the placebo cream.Conclusion:Enzymatic scavenging of the intracellular superoxide at ST 36 proved to be effective in decreasing SBP and DBP.The results reconfirm the involvement of superoxide anions and its transportation along the meridians,and demonstrate that EPD between acupoints may be an indicator to reflect its functioning status.Moreover,preliminary results suggest a close correlation between EPD and blood pressure readings,implying a possibility of using EPD as a sensitive parameter for blood pressure and to monitor the effect of antihypertensive treatment.