Marchal C, Anghileri L J, Escanye M C, Robert J
Int J Hyperthermia. 1986 Jan-Mar;2(1):83-92. doi: 10.3109/02656738609019997.
Recent studies indicate that differences in membrane fluidity may account for differences of thermal sensitivity. This possibility was studied by using lanthanum, a trivalent cation which is known to displace calcium in a number of biological systems, to modify the structural framework of cell membranes and consequently their biological properties. With Ehrlich ascites cells trypan blue exclusion uptake of 86Rb, 42K and 45Ca, indicate an increase of plasma cell permeability by La3+. The reduction of 86Rb and 42K uptake by tumour cells with La3+ appears to be independent of temperature. The increase of 45Ca2+ influx in the presence of lanthanum plus hyperthermia seems related to an important loss of cell viability. The enhancement of hyperthermia lethality by concentrations of lanthanum over 0.5 mM after 2 h at 44 degrees C has been demonstrated using HeLa S3 cells using a standard cloning technique. In vivo experiments have been performed on C3H mice bearing rhabdomyosarcoma using ultrasound heating at 44-46 degrees C. The results show a remarkable inhibition of tumour growth and a significant increase of the survival time after only one hyperthermia session of 30 min combined with one intratumoural injection of 1 mM lanthanum chloride.
最近的研究表明，膜流动性的差异可能是热敏感性差异的原因。通过使用镧（一种已知能在许多生物系统中取代钙的三价阳离子）来改变细胞膜的结构框架及其生物学特性，对这种可能性进行了研究。对于艾氏腹水细胞，用台盼蓝排斥法测定86Rb、42K和45Ca的摄取量，结果表明La3+可增加浆细胞膜通透性。La3+使肿瘤细胞对86Rb和42K的摄取减少，这似乎与温度无关。在镧存在且伴有热疗的情况下，45Ca2+内流增加似乎与细胞活力的显著丧失有关。使用HeLa S3细胞，采用标准克隆技术，已证明在44℃下2小时后，镧浓度超过0.5 mM可增强热疗致死率。对患有横纹肌肉瘤的C3H小鼠进行了体内实验，采用44 - 46℃的超声加热。结果显示，仅在30分钟的一次热疗疗程并结合一次瘤内注射1 mM氯化镧后，肿瘤生长受到显著抑制，存活时间显著延长。
