摘要
OBJECTIVE: To investigate gene expression of three nitric oxide synthase isozymes in injured spinal cord tissue. METHODS: Thirty-six adult SD rats were randomly divided into six groups: a normal group and five injury groups, with six per each group. Animals in the injury groups were sacrificed at 2, 6, 12, 24, 48 h after injury. A compression injury model on the spinal cord was made according to Nystrom B et al and gene expression of the three NOS isozymes were examined by reverse transcription polymerase chain reaction (RT-PCR). RESULTS: Gene expression of nNOS and eNOS were detectable in the normal group and were up-regulated quickly after injury, reaching a maximum at 6 h: (0.633 +/- 0.012) and (1.236 +/- 0.207). Gene expression of iNOS was detectable only in the injury groups and it was gradually up-regulated after injury, reaching a maximum at 24 h: (1.043 +/- 0.049). CONCLUSION: Injury to the spinal cord leads to early up-regulation of cNOS and late up-regulation of iNOS. Different NOS isozymes may play different roles in secondary spinal cord injury.
目的 探讨大鼠脊髓损伤后 3型一氧化氮合酶 (NOS)mRNA表达的变化规律。方法 36只成年SD大鼠 ,随机分为无损伤组和损伤后 2、6、12、2 4、4 8小时组 ,每组 6只 ,参照Nystrom的方法建立大鼠脊髓压迫伤模型 ,以逆转录聚合酶链反应 (RT PCR)法测定伤段脊髓组织神经型 (nNOS)、诱导型 (iNOS)及内皮型 (eNOS)一氧化氮合酶的mRNA表达情况。结果 正常脊髓组织中仅见nNOSmRNA及eNOSmRNA表达 ,未见iNOSmRNA表达 ;脊髓压迫伤后nNOSmRNA及eNOSmRNA表达增强 ,伤后早期 (6h)达到高峰 (0 6 33± 0 0 12 )、(1 2 36± 0 2 0 7) ;iNOSmRNA表达亦增高 ,但在后期 (2 4h)才达高峰 (1 0 4 3± 0 0 4 9)。结论 脊髓损伤后NOSmRNA的表达增强 ,但不同类型的NOSmRNA变化规律不同 ,不同NOS在脊髓继发性损伤中的作用可能不同。
基金
ThisworkwassupportedbytheNationalNaturalSciencesFoundationofChina (No 3 980 0 166)
