血卟啉衍生物(HpD)—激光对缺血小鼠肾脏的影响—光镜、组化和电镜观察

经尾静脉给雄性昆明小鼠注入HpD(10mg/kg体重),48小时后阻断肾动脉,造成缺血、缺氧的肾脏模型。然后用250—300J/cm~2剂量的630nm波长激光照射小鼠肾脏。最早出现的形态学改变是间质水肿和毛细血管破坏。近端小管上皮细胞在光照后6小时出现形态学改变,其它结构均在光照后24小时发生坏死。超微结构主要是线粒体、内质网和细胞核的破坏。肾酶的损伤程度为Cytox>AKP>ACP>SDH。实验结果表明,断血肾脏对血卟啉光动力学作用敏感性降低,但血管损伤加重。因此,血管损伤不是造成实质细胞损伤的始动因素,氧在血卟啉光动力学作用中是必需的。

Effects of HpD-laser on ischemic kidneys in mice(An observation with light microscopy, histochemistry and electron microscopy)

A dosage of 10 nig/kg of HpD was injected into the caudal veins of 26 male Kunming mice weighing 20-25g.Fourty-eight hours later,ischemic kidneys were made in all 36 animals, including 12 control ones, by blocking the renal artery for 15 minutes, and then the kidney areas were irradiated with the dye- laser for 10 minutes (630nm, 230-300J/cm2) . The earliest morphological changes in the kidneys were interstitial edema and capillary disruption .Six hours after dye laser the epithelial cells of the proximal tubules started to change. The distal tubule, collecting tubule and the renal corpuscles disrupted 24 hours after irradiation.Ultrastructural changes mainly took place in the mitochondria endoplasmic reticula and the nuclei.The severity of renal enzyme inhibition was in the following order. Cytox>AKP> ACP>SDH.The above results indicate that sensitivity of the ischemic kidneys to HpD-induced photodynamic effect is lowered with more serious and earlier damage in the capillaries. Therefore, vessel damage is not the motivating factor to produce necrosis of the cells.In addition, oxygen is an important factor in enhancing the occurrence of HpD-induced photodynamic injuries.