通过对小鼠S-180腹水瘤细胞DNA单链断裂及其重接的测定和细胞质膜对~(50)CrO_4~(2-)通透性的测定,探讨了光敏剂血卟啉衍生物(HPD)是否对X线增敏的问题。结果表明,在避光时HPD对X线的增敏作用不明显,但在自然光的照射下,HPD能增强X线的辐射效应,表现在DNA单链断裂重接的抑制和膜通透性的加强。对上述现象的原因进行了讨论。 Through the determination of DNA single strand breaks and reconnection in mouse S-180 ascites tumor cells and the determination of the permeability of ~ (50) CrO_4 ~ (2-) in the cytoplasmic membrane, the effects of photosensitizer hematoporphyrin derivatives HPD) is the problem of X-ray sensitization. The results showed that the effect of HPD on X-ray sensitization was not obvious when it was protected from light, but under the irradiation of natural light, HPD enhanced the radiation effect of X-ray. The effect of HPD on the inhibition of DNA single strand breaks and membrane permeability strengthen. The reasons for the above phenomenon are discussed.