丙酮酸钠在深低温停循环顺行选择性脑灌注中的脑保护作用

Brain protective effect of antegrade selective cerebral perfusion with sodium pyruvate in deep hypothermic circulatory arrest

目的探索在深低温停循环(DHCA)期间,顺行选择性脑灌注(ASCP)含丙酮酸钠(Pyr)的血液能否有效缓解氧化应激从而发挥脑保护作用。方法随机选取45只新西兰兔,18只作为供血兔,27只用于建立模型并随机分为:假手术(Sham)组(n=9)、ASCP组(n=9)和Pyr组(n=9)。Sham组麻醉后开胸,建立体外循环但不转机;Pyr组在DHCA中ASCP含Pyr溶液(154 mmol/L)与血液的混合液;ASCP组则为氯化钠溶液(154 mmol/L)与血液混合液。在麻醉后(T1)、降温至28℃(T2)、开放升主动脉后10 min(T3)、停机后10 min(T4)及停机后120 min(T5)五个时点采集血流动力学指标、检测动脉血气和采集颈静脉球部血液。停机后安乐死动物并进行脑组织取材。检测样本中丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性及S100B蛋白含量。结果 ASCP组MDA含量高于Sham组和Pyr组(P<0.05)。ASCP组SOD活性低于Sham组和Pyr组(P<0.05),与Pyr组在T3、T4和T5三个时点血浆S100B蛋白较组内T1时点高(P<0.05),ASCP组T3、T4和T5时点血浆S100B蛋白浓度显著高于同时点的Sham组和Pyr组(P<0.05)。结论 DHCA期间ASCP含外源性Pyr的血液可通过缓解氧化应激发挥较为完善的脑保护作用。

Objective To explore whether a combination of sodium pyruvate （ Pyr） and blood for antegrade selective cerebral perfusion （ASCP） during deep hypothermic circulatory arrest （DHCA） could attenuate oxidative stress and exert a better protective effect on the brain. Methods Fourty-five rabbits were selected randomly. Eighteen were used for blood donation, other rabbits used for model establishment and which were divided into：Sham group （n=9）, ASCP group （n=9） and Pyr group （n=9）. The Sham group underwent anesthesia and thoracotomy,set up cardiopulmonary bypass （ CPB） but no on pump. During DHCA, ASCP was performed with a combination of 154 mmol/L isotonic solution of sodium pyruvate and blood for Pyr group but a combination of 154 mmol/L Nacl solution and blood for ASCP group. Blood gas and hemodynamic parameters were measured in five time points during CPB. The rabbits ended with euthanasia after CPB, and their brain tissue were preserved. All samples were used to measure malondialdehyde （ MDA） content, superoxide dismutase （ SOD） activity and S100B content. Results he MDA content of ASCP group was higher than Sham group and Pyr group （ P〈0.05） . The SOD activity of ASCP group was lower than Sham group and Pyr group （ P〈0.05） . The S100B concentrations of ASCP group and Pyr group at T3, T4 and T5 points were higher than T1 point in the same groups （ P〈0.05） . The S100B concentrations of ASCP group at T3, T4 and T5 points were higher than Sham group and Pyr group at the same points （ P〈0.05） . Conclusion The combination of blood and sodium pyruvate for ASCP during DHCA could exert a better protective effect on the brain by attenuating oxidative stress.