关键词: 神经生长因子, 谷氨酸, 过氧化氢, 新型钙离子荧光指示剂(Fura-2), 细胞内游离钙

Abstract: The effects of nerve growth factor (NGF) on glutamate-and hydrogen peroxideinduced elevation of intracellular free Ca²⁺ concentration ([Ca²⁺]i) in isolated brain cells from neonatal rats were studied. [Ca²⁺]i was measured by calcium fluorescent indicator Fura 2-AM in a spectrofluorophotometer. The results showed that the resting [Ca²⁺]i was 208±22 nmol·L^-1 (When the brain cells were incubated in Hanks' solution containing Ca²⁺ 1.3 nmol·L^-1). NGF did not alter the resting [Ca²⁺]i (in brain cells). NGF 1, 3, 10, 30 and 100 μg·L^-1 dose-dependently attenuatedglutamate (0.5 mmol·L^-1) and hydrogen peroxide (0.05 mmol·L^-1)-induced elevation of [Ca²⁺]i by 10%, 18%, 32%, 44%, 62% and 14%, 30%, 39%, 49%, 65% and their IC50 were 42.5 and 27.3 (95% confidence limits: 28.7-71.5 and 18.1-46.5) μg·L^-1 respectively. These results indicate that NGF protects cortical neurons against glutamate toxicity and oxidative insult via reducing the elevation of [Ca²⁺]i may be one of the mechanisms of protective effect.

Key words: Nerve growth factor, Glutamate, Hydrogen peroxide, Fura-2, Intracellular free Ca2+