Dumoulin M J, Chahine R, Atanasiu R, Nadeau R, Mateescu M A
Department of Chemistry and Biochemistry, Université du Québec á Montréal, Canada.
Arzneimittelforschung. 1996 Sep;46(9):855-61.
The antioxidant effects of ceruloplasmin (CAS 9031-37-2) against oxygen free radicals (.O2-, .OH, 1O2) and their by-products (H2O2, HOCl), generated by electrolysis of Krebs-Henseleit buffer, were determined in vitro by the DPD (N,N-diethyl-p-phenylenediamine) colorimetric method and ex vivo by quantifying cardiodynamic variables of the isolated perfused rat heart. Purified ceruloplasmin (1 mumol/l) displayed a high antioxidant capacity in vitro (89.2%), while the scavenging capacity of superoxide dismutase (SOD) in equimolar concentrations was 38.1%. A relatively high scavenging activity (72.1%) was observed with bovine serum albumin (BSA). A control group of Langendorff isolated rat hearts (n = 8) was submitted to electrolysis (10 mA, for 1 min) without treatment, whereas the treated groups were perfused with ceruloplasmin, SOD or BSA (1 mumol/l) in the inflow cannula for 5 min before, during, and 5 min after electrolysis. The cardioprotective effect afforded by ceruloplasmin (83-89%) was higher than that observed with the same optimal dose of 1 mumol/l SOD (20-45%). With BSA, no protection was observed ex vivo. Particularities in scavenging specificities and mechanisms seem to explain the important differences between in vitro and ex vivo antioxidant capacities for these proteins.
采用二氨基二乙基苯胺（DPD）比色法在体外测定了铜蓝蛋白（CAS 9031-37-2）对克雷布斯-亨泽莱特缓冲液电解产生的氧自由基（·O₂⁻、·OH、¹O₂）及其副产物（H₂O₂、HOCl）的抗氧化作用，并通过定量离体灌注大鼠心脏的心脏动力学变量在体内进行了测定。纯化的铜蓝蛋白（1 μmol/L）在体外显示出较高的抗氧化能力（89.2%），而等摩尔浓度的超氧化物歧化酶（SOD）的清除能力为38.1%。观察到牛血清白蛋白（BSA）具有相对较高的清除活性（72.1%）。一组朗格多夫离体大鼠心脏（n = 8）未经处理接受电解（10 mA，持续1分钟），而处理组在电解前、电解期间和电解后5分钟，在流入插管中用铜蓝蛋白、SOD或BSA（1 μmol/L）灌注5分钟。铜蓝蛋白提供的心脏保护作用（83 - 89%）高于相同最佳剂量1 μmol/L的SOD所观察到的保护作用（20 - 45%）。使用BSA时，在体内未观察到保护作用。清除特异性和机制的特殊性似乎可以解释这些蛋白质在体外和体内抗氧化能力之间的重要差异。
