Oyama Y, Chikahisa L, Matoba H, Furukawa K
Laboratory of Cell Signalling--Pharmacology, Faculty of Integrated Arts and Sciences, University of Tokushima, Japan.
Brain Res. 1994 Nov 21;664(1-2):220-4. doi: 10.1016/0006-8993(94)91975-5.
Effects of cooling and calmodulin antagonist on ionomycin-induced increase in oxidative metabolism (or formation of reactive oxygen species) of rat cerebellar neurons was examined using a flow cytometer and 2',7'-dichlorofluorescin diacetate, a fluorescent dye for intracellular hydrogen peroxide. Cooling neurons to temperatures below 16 degrees C greatly attenuated ionomycin-induced augmentation of oxidative metabolism without affecting the Ca2+ influx produced by ionomycin. Rewarming neurons to 36 degrees C in presence of ionomycin increased the oxidative metabolism, indicating a temperature-sensitive metabolic process. Substitution of Ca2+ with Ba2+ or Sr2+ completely abolished an ionomycin-induced increase in the oxidative metabolism. Pretreatment with W-7, a calmodulin antagonist, at concentrations of 10 microM or higher (up to 100 microM) produced a dose-dependent attenuation of ionomycin-induced increase in oxidative metabolism. Results suggest that calmodulin is involved in the ionomycin-induced increase in oxidative metabolism of dissociated cerebellar neurons.
使用流式细胞仪和2',7'-二氯荧光素二乙酸酯（一种用于检测细胞内过氧化氢的荧光染料），研究了冷却和钙调蛋白拮抗剂对离子霉素诱导的大鼠小脑神经元氧化代谢增加（或活性氧形成）的影响。将神经元冷却至16摄氏度以下的温度可极大地减弱离子霉素诱导的氧化代谢增强，而不影响离子霉素产生的Ca2+内流。在离子霉素存在的情况下将神经元复温至36摄氏度会增加氧化代谢，表明这是一个对温度敏感的代谢过程。用Ba2+或Sr2+替代Ca2+可完全消除离子霉素诱导的氧化代谢增加。用钙调蛋白拮抗剂W-7以10微摩尔或更高浓度（高达100微摩尔）进行预处理，可使离子霉素诱导的氧化代谢增加产生剂量依赖性减弱。结果表明，钙调蛋白参与了离子霉素诱导的离体小脑神经元氧化代谢增加。
