摘要：目的 观察并寻找适宜新生大鼠背根神经元生长的最佳他克莫司(FK506)浓度.方法 取8只新生24 h SD大鼠的背根神经节,剥除神经外膜,剪成约0.1 mm~3大小的碎块,消化后进行纯化培养,建立体外新生大鼠脊髓背根神经元培养体系.培养96 h后,将背根神经元分为:空白对照组(A组)、1×10~(-10) mol/L FK506组(B组)、1×10~(-9)mol/L FK506组(C组)和1×10~(-8)mol/L FK506组(D组).继续培养48 h后,应用甲基噻唑基四唑(MTT)比色法检测细胞活力及逆转录酶-聚合酶链式反应法(RT-PCR)检测生长相关蛋白-43(GAP-43)mRNA的表达情况.比较4组神经元活力和GAP-43 mRNA的表达情况.结果 A、B、C、D组的OD值分别为0.472±0.030、0.481±0.013、0.573±0.016、0.342±0.004,4组之间比较差异有统计学意义(F=26.753,P<0.01),C、D两组之间比较及C、D组分别与A、B组比较,差异均有统计学意义(P<0.05).A、B、C、D组的GAP-43 mRNA的表达值分别为0.375±0.016、0.388±0.009、0.490±0.003、0.283±0.009,4组之间比较差异有统计学意义(F=72.374,P<0.01),C、D两组之间比较及C、D组分别与A、B组比较,差异均有统计学意义(P<0.05).结论 1×10~(-9)mol/L浓度的FKS06对大鼠脊髓背根神经元生长的促进和保护作用最好,1×10~(-10)mol/L浓度的FK506对大鼠脊髓背根神经元生长具有促进和保护作用,1×10~(-8)mol/L浓度的FK506对神经元的生长具有抑制作用.
Abstract：Objective To determine the concentrations of FK506 suitable to the growth of the dorsal root ganglia neuron (DRGn). Methods The dorsal root ganglia (DRG) of 8 new-born SD rats (within 24 hours) were collected to remove the epineurium of the DRG. After dissection into pieces of about 0.1 mm~3 in size, the DRG fragments were digested by 0.25% trypsin. Then DRGn was purified and cultured for 96 hours before establishment of 4 groups: blank-control group (Group A), 1×10~(-10) mol/L FK506 (Group B), 1× 10~(-9) mol/L FK506 (Group C) and 1×10~(-8) mol/L FK506 (Group D). After culture of the DRGn for another 48 hours, the growth of neurons was assessed by NF200 immunofluorescence, the vitality of the DRGn by MTT method and the expression of GAP-43's mRNA by RT-PCR. Results The MTT value and GAP-43mRNA expression in group A were respectively 0.472±0.030 and 0.375±0.016, in group B were respectively 0.481±0.013 and 0.388±0.009, in group C were respectively 0.573±0.016 and 0.490±0.003, and in group D were respectively 0.342±0.004 and 0.283±0.009. There were no statistical significances between groups A and B (P>0.05), but when group A was compared with groups C and D, statistical significances existed (P< 0.05). The statistical significances also existed when group B was compared with groups C and D (P<0.05). There were statistical significances between groups C and D (P<0.05) . Conclusions The 1×10~(-9) mol/L concentration of FK506 may provide best neurotrophy and neuroprotection for the growth of DRGn. FK506 of 1×10~(-10) mol/L may also provide neurotrophy and neuroprotection for the growth of DRGn, but FK506 of 1×10~(-8) mol/L may have inhibitory effects on the neurons.