Milanesi C, Sorgato F, Jori G
Department of Biology, University of Padova, Italy.
Int J Radiat Biol. 1989 Jan;55(1):59-69. doi: 10.1080/09553008914550071.
Liposome-bound haematoporphyrin or haematoporphyrin dimethylester, as well as haematoporphyrin dissolved in phosphate-buffered saline, were added to HeLa cell monolayers at a dose of 1 microgram of porphyrin per 10(5) cells. After 2 min or 20 min incubation liposome-bound porphyrins were accumulated by cells in an about two-fold larger amount than the water-dissolved haematoporphyrin. This caused a more efficient photosensitization of HeLa cells by liposome-delivered porphyrins upon illumination with 366 nm light. Ultrastructural studies of HeLa cells, which had been incubated in a physiological medium for 24h after the end of irradiation, showed that liposomal porphyrins induce an early and extensive endocytoplasmic damage, leading to swelling of the mitochondria and vesiculation; changes of the permeability of the cytoplasmic membrane are also evident, especially in the case of haematoporphyrin dimethylester. On the other hand, water-dissolved haematoporphyrin predominantly photosensitizes damage of the plasma membrane. The different pattern of cell photodamage probably reflects a different subcellular distribution of the photosensitizing drugs.
将脂质体结合的血卟啉或血卟啉二甲酯，以及溶解于磷酸盐缓冲盐溶液中的血卟啉，以每10⁵个细胞1微克卟啉的剂量添加到HeLa细胞单层中。孵育2分钟或20分钟后，细胞积累的脂质体结合卟啉量比水溶性血卟啉大约多两倍。这使得在用366nm光照射时，脂质体递送的卟啉对HeLa细胞的光致敏作用更有效。对照射结束后在生理培养基中孵育24小时的HeLa细胞进行的超微结构研究表明，脂质体卟啉会引起早期广泛的胞质内损伤，导致线粒体肿胀和形成囊泡；细胞质膜通透性的变化也很明显，尤其是血卟啉二甲酯的情况。另一方面，水溶性血卟啉主要使质膜发生光致敏损伤。细胞光损伤的不同模式可能反映了光敏药物在亚细胞水平的不同分布。
