用23Na NMR研究竹红菌乙素光敏损伤对鼠腹水肝癌细胞Na+通透性的影响

用²³Na NMR技术并借助于水溶性位移试剂Dy(PPPi)₂^7-研究了新型光敏剂-竹红菌乙素光敏损伤对鼠腹水肝癌细胞Na⁺通透性的影响。实验结果表明:在乙素光敏作用下,细胞内Na⁺浓度随曝光时间的延长和乙素浓度增高而增加。同时观察到细胞外²³Na_out NMR峰的化学位移(δ值)随光照时间增加而向低场位移。分析表明:化学位移的改变与细胞膜损伤引起细胞内K⁺泄漏和K⁺、Na⁺竞争位移试剂有关。因此,化学位移的改变也可作为光敏损伤的指标。本文还就Na⁺平衡失调与细胞死亡之间的关系进行了讨论。

THE EFFECT OF HB-PHOTOSENSITIZED DAMAGE ON Na+ PERMEABILITY OF MOUSE ASCITIC HEPATOMA CELLS

In this paper ²³Na NMR technique with shift reagent Dy(PPPi)₂^7- was used to study a new type of photosensitizer-Hypocrellin B which photosensitized damage on Na⁺ permeability of ascitic hepatoma cells. The experimental results show that intracellular Na⁺ concentration increases with both light dose and photosensitizer concentration. It was also observed that the chemical shift of ²³Na_out NMR peak moved to downfieid as illumination time was increased in the presence of HB.Analysis indicates that the changes of chemical shift relate to the loss of intraceilular K⁺ and K⁺ competes with Na⁺ for shift reagent. Therefore, the changes of chemical shift may be an index of photosensitized damage. The relation between the increase of Na⁺ concentration and cell death was discussed.