目的既往研究表明,孤啡肽在脑损伤后的表达明显升高,本研究通过特异性阻断孤啡肽受体(opioid-receptor-like receptor,ORL-1),观察对受损神经元是否具有保护作用。方法建立神经元机械性损伤模型,用孤啡肽受体特异性阻断剂([Nphe1]-NC(1-13)-NH2,Nphe)阻断孤啡肽受体,通过四甲基偶氮唑蓝(methyl thiazolyl tetrazolium,MTT)法、乳酸脱氢酶(lactate dehydrogenase,LDH)活性,钙离子水平测定,研究Nphe对机械性损伤神经元存活率的影响。结果 MTT法测定神经元机械性损伤后12 h细胞存活率显示:单纯损伤组细胞存活率为46%±4%,与对照组相比显著下降(P〈0.05),不同剂量Nphe(30、300、1 200 nM)干预组的细胞存活率分别为56%±5%、67%±7%、72%±8%,与单纯损伤组存活率46%±4%相比差异显著(P〈0.05)。LDH活性检测提示损伤后12 h和48 h,Nphe干预组LDH活性与损伤组相比有显著差异(P〈0.05)。神经元机械性损伤后12 h,Nphe能够降低损伤后细胞内钙离子水平(P〈0.05)。结论 ORL-1的特异性拮抗剂Nphe能够减少机械性损伤后继发性神经元损害,对神经元具有一定的保护作用。
Objective Earlier study showed that orphanin FQ was increased significantly after traumatic brain injury.This study aims to investigate whether blocking of the orphanin receptor(ORL-1) affects neuronal viability after traumatic neuronal injury.Methods Mechanic injury neuronal model was established.The neuroprotective effects of [Nphe1]-NC(1-13)-NH2(Nphe),an antagonist of ORL-1,on injured neurons were observed by methyl thiazolyl tetrazolium(MTT) assay,detection of activity of the lactate dehydrogenase(LDH) and calcium level.Results Nphe increased the neuronal viability in a dose-dependent manner after traumatic neuronal injury in vitro measured by MTT assay.Different dose of Nphe(30 nM,300 nM,1 200 nM) increased the neuronal viability(56%±5%,67%±7%,72%±8%) compared with injury group(46%±4%,P0.05).And Nphe produced a decrease in intra-cellular calcium level at 12 h(P0.05) and LDH concentrations at 12 h,48 h(P0.05).Conclusion As an antagonist of the OFQ receptor,Nphe can improve neuronal viability in cultured neurons from rat embryonic cortex after traumatic neuronal injury.