Protective effects of scutellarin on superoxide-induced oxidative stress in rat cortical synaptosomes  

灯盏花乙素对超氧阴离子引起的大鼠脑突触体氧化应激的保护作用

作　　者：刘宏[1] 杨祥良[1] 王影[1] 唐晓荞[1] 江冬英[1] 徐辉碧[1] 

机构地区：[1]华中科技大学药物研究所，中国武汉430074

出　　处：《Acta Pharmacologica Sinica》2003年第11期1113-1117,1174,共6页中国药理学报（英文版）

基　　金：Project partly supported by the Ministry of Science and Technology of China (2001BA310A07).

摘　　要：AIM: To evaluate the effects of scutellarin on superoxide-induced oxidative stress in rat cortical synaptosomes. METHODS: Oxidative damage model was established by incubation with xanthine（0.3 mmol/L） and xanthine oxidase（0.02U） at 37℃ for 30 min. The extent of membrane oxidation was assessed by malondialdehyde （MDA）. Membrane fluidity was measured by fluorescence anisotropy（polarization） of the lipophilic probe 1,6-diphenyl-1,3, 5-hexatriene（DPH）. Intracellular Ca²⁺ concentration([Ca²⁺]_i) was measured by fluorescent spectrophotometry. Fura 2-AM was used as an indicator for [Ca²⁺]_i. Na⁺/K⁺-ATPase activity assay was based on the amount of inorganic phosphate（Pi） released during an enzymatic hydrolysis of ATP. RESULTS: Synaptosomes exposed to superoxide significantly elevated the levels of malondialdehyde（MDA） and [Ca²⁺]_i compared with those in normal group. These changes were accompanied by the decrease in membrane fluidity and Na⁺/K⁺-ATPase activity. Pretreatment with scutellarin（25-100μmol/L） significantly ameliorated the oxidative damage of synaptosomes by reducing MDA levels and [Ca²⁺]_i, up-regulating membrane fluidity and restoring Na⁺/K⁺-ATPase activity. CONCLUSION: Scutellarin exerts a potent protective effect against oxidative damage in synaptosomes induced by superoxide.目的：研究灯盏花乙素对超氧阴离子引起的大鼠脑突触体氧化应激的保护作用．方法：采用与黄嘌呤(0．3mmol／L)和黄嘌呤氧化酶(0．02U)体系在37℃下孵育30min，建立大鼠脑突触体超氧阴离子氧化损伤模型．通过测定脂质过氧化产物丙二醛评价脂质过氧化程度．通过脂溶性荧光探针DPH的各向异性判断突触体膜的流动性．胞内钙离子的测定采用荧光光度法，以Fura2-AM为荧光探针．测定ATP酶解释放的无机磷确定Na^+／K^+-ATP酶的活性．结果：超氧阴离子使大鼠脑突触体的脂质过氧化产物丙二醛及胞内钙离子浓度显著上升，突触体的膜流动性和Na^+／K^+-ATP酶的活性则显著下降，预先加入灯盏花乙素(25-100μmol／L)则能显著缓解超氧阴离子引起的氧化性损伤，表现为丙二醛的水平和胞内钙离子浓度下降，膜流动性增加及Na^+／K^+-ATP酶活性的恢复．结论：灯盏花乙素对超氧阴离子引起的大鼠脑突触体氧化应激具有良好的保护作用．

关 键 词：SCUTELLARIN SYNAPTOSOMES MALONDIALDEHYDE membrane fluidity calcium Na^(+)-K^(+)-exchanging ATPase 

分 类 号：R285[医药卫生—中药学]