Neuroprotective Effects of some drugs on adult rat brain following central auditory tract axotomy

氧化应激和氧源性自由基如一氧化氮（NO）的大量产生可能是中枢和/或外周神经损伤后神经元细胞死亡的最重要机制之一。本研究旨在探讨重组人促红细胞生成素（rhEPO）和粒细胞集落刺激因子（G-CSF）对脑干神经损伤后受损面神经核（FMN）和外侧丘系背核（DNLL）的神经保护作用。与健侧相比，FMN中运动神经元的存活率在第14天和第28天分别为25.0±2.4%和2.8±1.4%。注射rhEPO（5000 U/kg/d）后，FMN运动神经元存活率在第14天为42.6±6.7%，第28天为8.2±0.5%。大部分的对侧投射神经元的DNLL进行逆行变性的第14天。G-CSF（50 μ g/kg/d）治疗14天后，DLL神经元存活率为50%，提示rhEPO和G-CSF对脑干轴突切断后FMN和DNLL的退行性变性具有神经保护作用。

oxidative stress and massive production of oxygen-derived free radicals such as nitric oxide(NO) might be one of the most important mechanisms of neuronal cell death following central and/or peripheral nerve injury. This study was aimed to investigate whether recombinant human erythropoietin(rhEPO) and granulocyte colony stimulating factor(G-CSF) exert their neuroprotective effect on the lesioned facial nucleus(FMN) and the dorsal nucleus of lateral lemniscus(DNLL) after nerve injury in the brainstem.1.After the facial nerve axotomy in the brainstem according to stereotaxic coordinates, the survival ratio of motoneurons in the FMN was 25.0±2.4% on day 14 and 2.8±1.4% on day 28 compared to the contralateral intact side. The survival ratio of motoneurons in the FMN with the rhEPO administration (5000 U/kg daily) was 42.6±6.7% on day 14 and 8.2±0.5% on day 28.2.The commissure of Probst was transected through its midline decussation with micro knife inserted into the brain according to stereotaxic coordinates. Most of the contralaterally projecting neurons of the DNLL underwent retrograde degeneration on day 14. The survival ratio of the DLL nuerons with the G-CSF administration (50ug/kg daily) was 50% on day 14.These findings suggest that rhEPO and G-CSF have neuroprotective property to the retrograde degeneration of the FMN and the DNLL after axotomy in the brainstem.