用稳态荧光探针研究竹红菌乙素光敏损伤对人红细胞膜流动性的影响

INVESTIGATION OF HYPOCRELLIN B SENSITIZED PHOTODAMAGE TO THE FLUIDITY OF ERYTHROCYTE MEMBRANE

本文以红细胞膜为材料,用了三种稳态荧光探针研究了HB光敏作用引起人红细胞膜流动性的改变.实验结果表明在HB光敏作用下,膜的旋转扩散速度和侧向扩散速度均发生明显变化,ANS和DPH探针测得HB引起膜流动性降低,也就是膜粘度增加,用芘探针结果则表明膜的侧向扩散变慢.本文还对HB光敏作用的机理进行了探讨,我们观察了数种单重态氧猝灭剂,羟自山基猝灭剂和抗氧化剂对于光敏作用的影响,分别测定了膜流动性和膜的内源荧光的变化,发现在HB光敏作用中,除了~1O_2的作用之外,还存在其它自由基的作用.在HB与HA光敏能力的比较中发现,在比较高一些浓度条件下,存在着HB大于HA的趋向.

Three static fluorescence probes: 1, 6-diphenyl-1, 3, 5-hexatriene (DPH), l-anilino-8-naphthalene sulffonate (ANS) and pyrene were used to study the fluidity of erythrocyte membrane.We found that the degree of polarization increased, after visible light illumination in the presence of Hypocrellin B. It means that the membrane fluidity and the lateral diffusion rate decreased (by measuring pyrene excimer/monomer ratio) with increasing concentration of hypocrellin B.To elucidate the mechanism of photodamage of hypocrellin B in biological systems, 1O2 quenchers such as, 1, 4-diazabicyclo (2, 2, 2) octane; L-histidine; OH- radical quencher: N-(p-AminoBenzoyl) -L-Glutamic Acid(PABGA); antioxi-dant: Butylated hydroxytoluene (BHT)reagent and Deuterium solvent effects were investigated. The results showed that the photodamages to fluidity of erythrocyte membranes were not only due to the simple mechanism of 1O2; but also due to other radicals as well. We also compared the effect of different concentrations of HB and HA on the polarizability of erythrocyte membranes it was found that the effect of HB was greater than that of HA when the concentrations were more that 4×10-8M.