纳洛酮对缺氧大鼠皮质神经元的保护作用

背景纳洛酮对脑缺血再灌注损伤细胞的保护作用机制尚不明确.选择体外培养皮质神经元研究纳洛酮疗效可排除多重因素干扰.目的观察缺氧对体外培养大鼠皮质神经元的影响及纳洛酮的保护机制.设计重复测量设计.地点和对象实验地点军事医学科学院神经生物学研究室.研究对象体外培养12d的Wistar大鼠皮质神经元.干预取体外培养12 d的Wistar大鼠皮质神经元,随机分为正常对照组、缺氧组、纳洛酮组(缺氧前24h加纳洛酮预处理);缺氧6 h后在常氧下继续培养24 h.主要观察指标观察各种条件下神经元的存活率和形态学的改变,测定培养液中乳酸脱氢酶(LDH)含量.结果缺氧后可见神经元胞体肿胀、细胞死亡,LDH渗出量增多[6h正常对照组为(78.68±7.34)%,缺氧组为(194.38 ±22.32)%;12 h正常对照组为(77.98±8.85)%,缺氧组为(331.66±36.12)%],细胞存活率减少[6h正常对照组为(91.82±2.89)%,缺氧组为(66.96±4.98)%;12 h正常对照组为(90.84±2.61)%,缺氧组为(32.02±6.34)%],差异有显著性意义(P＜0.01).经纳洛酮预处理的神经元,缺氧后神经元胞体肿胀、细胞死亡程度轻于缺氧组,LDH渗出[6h(159.86±34.03)%;12 h(256.28±28.29)%]显著低于缺氧组(P＜0.01),而存活率[6h(78.08±4.15)%;12 h(53.68±4.32)%]明显高于缺氧组,差异有显著性意义(P＜0.01).结论对缺氧诱导的皮质神经元的损伤,纳洛酮具有明显的保护作用.

Protective effect of naloxone on cortical neurons in hypoxia rats

BACKGROUND:The mechanism of protective effect of naloxone on the injured cells of cerebral isehemical reperfusion is not quiet clear. Multiple interactive factors can be excluded when the therapeutic effect of naloxone is studied with cortical neurons cultured in vitro.OBJECTIVE: To observe the influence of hypoxia on rat cortical neurons cultured in vitro and study the protective mechanism of naloxone.DESIGN: Design of replicate-measurements.SETTING and MATERIALS: Setting: Department of Neurobiology, Academy of Military Medical Sciences. Materials: Cortical neurons of Wistar rats cultured in vitro for 12 days .INTERVENTIONS: Cortical neurons of Wistar rats cultured in vitro for 12days were randomly divided into normal control group, hypoxia group, and naloxone group(pretreated with naloxone 24 hours before hypoxia treatment); and continued to culture for 24 hours under normoxia after hypoxia for 6 hours.MAIN OUTCOME MEASURES: Survival rate of neurons in various conditions and the morpbological changes were observed, and lactic dehydrogenase(LDH)content in culture fluid was measured.RESULTS: Cell body swelling and death could be found after hypoxia treatment, exflltration content of LDH increased[6 hours: normal control group (78.68 ±7.34)%, hypoxia group(194.38 ±22. 32)%;12 hours:normal controlgroup(77.98 ±8.85)%, hypoxia group(331.66 ±36. 12)%],survival rate of neurons reduced[6 hours: normal controlgroup(91.82± 2.89)％, hypoxia group(66. 96 ±4.98)%; 12 hours: normal control group(90. 84 ±2.61)%, hypoxia group(32.02 ±6.34)％ ], and the difference was significant( P< 0.01 ). In naloxone pretreated group, extent of cell body swelling and death after hypoxia was slightly lower than that of hypoxia group, and LDH content [6 hour:(159. 86 ±34.03);12 hours:(256.28 ±28.29)％ ] was significantly more decreased than that of the hypoxia ones( P<0.01 ),while survival rate[6 hours: (78.08 ± 4. 15)％;12 hours:(53.68±4.32)%] was markedly higher than that of hypoxia group,and the difference was significant (P<0. 01) .CONCLUSION: Hypoxia can induce damage of cortical neurons,and naloxone has significant protection on the damage of neurons induced by hypoxia.