Himmelseher S, Pfenninger E, Georgieff M
Department of Anesthesiology, University Hospital of Ulm, Germany.
Crit Care Med. 1998 Dec;26(12):2029-36. doi: 10.1097/00003246-199812000-00035.
To evaluate the long-term effects of lactic acidosis and to examine a potential neuroprotective role of basic fibroblast growth factor (bFGF) on hippocampal neurons.
Long-term observation in a cell-culture study.
University research laboratory.
Adult, differentiated, primary rat hippocampal neurons.
Neurons were exposed to medium acidified with 20 mM lactic acid, pH 6.2, for a 10-min period, and maintained untreated or in the presence of bFGF (500 pg/mL, 1 ng/mL, 10 ng/mL, 20 ng/mL) applied after exposure.
Viability was analyzed by a dye inclusion/enzyme activity test and morphology by phase contrast and immunofluorescence microscopy. [3H]Arachidonic acid (AA) release was measured by liquid scintillation spectrometry. All cultures appeared to be unchanged during the first days after exposure to lactic acidosis. Neurodegeneration became apparent within 3 days. Seven days after exposure, cell survival decreased to 60% in lactic acidosis-injured, untreated cultures. Morphologic damage appeared as a 50% reduction in axonal and 25% reduction in dendritic arborizations. AA release increased to four-fold enhanced levels relative to control values. bFGF (1, 20, and 10 ng/ mL) enhanced neuronal viability (p < .05), and 10 ng/mL bFGF induced a maximal increase in live cells to 80% of controls. Axonal arborizations increased to 50% and dendritic arborizations to 75% of controls after 10 ng/mL bFGF (p< .05). bFGF in a dose of 20 ng/ mL enhanced axonal branching to 40% and dendrites in number and branching to 50% of controls (p< .05). bFGF (500 pg/mL, and 1 and 10 ng/mL) decreased enhanced AA (p < .05), and 10 ng/mL bFGF maximally reduced increased AA to two-fold enhanced values relative to controls.
In vulnerable neurons, exposure to moderate lactic acidosis induces a process of cell injury with long latency. bFGF applied postinjury reduces the delayed neurodegeneration and may have neuroprotective efficacy in new therapeutic strategies to ischemia-induced cerebral injury.
评估乳酸酸中毒的长期影响，并研究碱性成纤维细胞生长因子（bFGF）对海马神经元的潜在神经保护作用。
细胞培养研究中的长期观察。
大学研究实验室。
成年、分化的原代大鼠海马神经元。
将神经元暴露于用20 mM乳酸酸化至pH 6.2的培养基中10分钟，然后在暴露后不进行处理或在存在bFGF（500 pg/mL、1 ng/mL、10 ng/mL、20 ng/mL）的情况下进行培养。
通过染料摄取/酶活性测试分析细胞活力，通过相差显微镜和免疫荧光显微镜观察形态。通过液体闪烁光谱法测量[³H]花生四烯酸（AA）释放。在暴露于乳酸酸中毒后的头几天，所有培养物似乎都没有变化。3天内神经退行性变变得明显。暴露7天后，乳酸酸中毒损伤且未处理的培养物中细胞存活率降至60%。形态学损伤表现为轴突减少50%，树突分支减少25%。AA释放相对于对照值增加至四倍。bFGF（1、20和10 ng/mL）提高了神经元活力（p < 0.05），10 ng/mL bFGF使存活细胞数量最大增加至对照的80%。10 ng/mL bFGF处理后，轴突分支增加至对照的50%，树突分支增加至对照的75%（p < 0.05）。20 ng/mL剂量的bFGF使轴突分支增加至对照的40%，树突数量和分支增加至对照的50%（p < 0.05）。bFGF（500 pg/mL、1和10 ng/mL）降低了升高的AA水平（p < 0.05），10 ng/mL bFGF最大程度地将升高的AA降低至相对于对照增加两倍的值。
在易损神经元中，暴露于中度乳酸酸中毒会诱导一个潜伏期较长的细胞损伤过程。损伤后应用bFGF可减少延迟性神经退行性变，在缺血性脑损伤的新治疗策略中可能具有神经保护作用。
