经皮穴位电刺激复合药物全麻行控制性降压对心功能及心肌抗氧化能力的影响

Effects of transcutaneous electrical acupoint stimulation combined with general anesthesia for controlled hypotension on heart function and oxidation resistance of myocardium

目的:观察行控制性降压至极限水平时,经皮穴位电刺激(TEAS)对心脏的干预效应。方法:18只雄性清洁级比格犬随机分为单纯全麻组、对照组和实验组,每组6只。3组动物均行全麻处理,其中对照组和实验组动物均以异氟烷联合硝普钠行控制性降压至基础平均动脉压30%(30%MAP)水平并维持60 min,仅实验组选用双侧"合谷""曲池""足三里""三阴交"穴行TEAS,刺激强度6～8mA,频率2Hz/100Hz,在实验动物生理状态稳定后开始至维持目标MAP 60min时停止。观察3组动物基础及术后2h、24h、48h、72h血清肌酸激酶同工酶(CK-MB)活力及乳酸脱氢酶(LDH)活性变化,并观察术后72h时心肌组织总超氧化物歧化酶(T-SOD)活力、丙二醛(MDA)含量变化。结果:术后24h时各组动物LDH活性表达达到高峰,以后逐渐恢复,至术后72h时,与本组基础水平比较,对照组动物LDH活性显著增高(P<0.05),而全麻组、实验组无统计学差异(P>0.05);术后2～24h时,各组动物CK-MB活力表达达到高峰,以后逐渐恢复,与本组72h比较,对照组48h显著增高(P<0.05),单纯全麻组和实验组无统计学差异(P>0.05);行控制性降压术后72h,对照组心肌MDA含量明显高于单纯全麻组与实验组(P<0.05)。结论:TEAS复合药物全麻行控制性降压可能通过提高心肌的抗氧自由基能力,减少术后LDH、CK-MB释放,从而达到心肌保护作用。

To investigate the intervention effect of transcutaneous electrical acupoint sitmulation （TEAS） on heart under limiting level of controlled hypotension. Methods Eighteen male Beagles were randomly divided into a general anesthesia group, a control group and an experimental group, 6 dogs in each group. All ani- mals were applied with general anesthesia, and the animals of the control group and the experimental group were administered with combination of isoflurane and sodium nitroprusside （SNP） for controlled hypotension to 30% mean arterial pressure （30%MAP） of base line for 60 rain. In the experimental group, TEAS （2 Hz/100 Hz, 6- 8 mA） was applied to ＂Hegu＂ （LI 4）, ＂Zusanli＂ （ST 36）, ＂Sanyinjiao＂ （SP 6） and ＂Quchi＂ （LI 11） from the be- ginning of physiological conditions stability to the end of maintained low MAP for 60 min. Creatine kinase isoenzymes MB （CK-MB） and lactate dehydrogenase （LDH） activity were detected at the base line and 2 h, 24 h, 48 h, 72 h after operation. Total superoxide dismutase iT-SOD） and malondialdehyde （MDA） in myocardium were observed at 72 h after operation. Results The peak of LDH arrived at 24 h after operation and then restored in 3 groups. Compared with basal level, the activity of I.DH in controlled group at 72 h after operation was signifi- cantly increased （P〈0.05）, and in the other two groups no obvious change （P〉0.05）. The activity of CK-MB arrived to peak from 2 h to 24 h after operation, and then came back gradually in 3 groups. Compared with postop- erative 72 h of the same group, the control group at 48 h significantly increased （P〈0.05）, while the other two groups had no statistically significant difference （P〉0.05）. The content of MDA at 72 h after operation in con- trolled group was higher significantly than that in the general anesthesia group and the experimental group （both P〈0.05）. Conclusion TEAS combined with anesthesia for controlled hypotension can elevate myocardial effect ofanti-oxide free radical, reduce the postoperative release of LDH and CK-MB, so as to produce myocardial protec tion.