Calpain抑制剂Ⅰ对大鼠脑非断离性轴索损伤继发断离的影响

Effects of calpain inhibitor Ⅰ on secondary axotomy of nondisruptive axonal injury after diffused brain injury in rats

目的 研究Calpain抑制剂Ⅰ对非断离性轴索损伤 (NDAI)继发断离的影响 ,探讨NDAI的治疗途径。 方法 将 16只雄性SD大鼠随机分为Calpain抑制剂Ⅰ组和对照组各 8只 ,液压冲击致大鼠脑弥漫性损伤 ,比较两组伤后 2 4 ,72h胼胝体区、间脑中脑区、桥脑延脑区和小脑区肿胀轴索及轴索球最大密度变化。 结果 大鼠致伤后 ,NF6 8免疫组化显示肿胀的轴索及轴索球。伤后 2 4h ,Calpain抑制剂Ⅰ组桥脑延脑区、小脑区肿胀轴索及轴索球最大密度明显减少 (P <0 .0 1) ;伤后 72h ,Calpain抑制剂Ⅰ组小脑肿胀轴索及轴索球减少 (P <0 .0 5 ) ,而胼胝体区、间脑中脑区、桥脑延脑区变化不明显 (P >0 .0 5 )。 结论 Calpain抑制剂Ⅰ可减轻NDAI的继发断离 ,主要是减少损伤较轻的NDAI的继发断离。

Objective To investigate the effects of Calpain inhibitor Ⅰ on the secondary axotomy of nondisruptive axonal injury (NDAI) after diffused brain injury (DBI) in rats and discuss the way to prevent NDAI from secondary axotomy. Methods A total of 16 male Sprague-Dawley rats were randomly and equally divided into control group and Calpain inhibitor Ⅰ group. The axonal swellings and axonal balls were detected by NF68 immunochemistry after DBI caused by fluid percussion. The changes of maximal density of axonal swellings and axonal balls in calosum, diencephalon-mesencephalon, pons-oblongata and cerebellum were compared between both groups 24 and 72 hours respectively after injury. Results NF68 immunoche mistry showed swelled axons and axonal balls after injury. In Calpain inhibitor I group, the maximal density of axonal swellings and axonal balls in the pons-oblongata and the cerebellum was obviously decreased 24 hours after injury (P<0.01). At the 72nd hour after injury, the maximal density of axonal swellings and axonal balls significantly decreased only in the cerebellum (P<0.05), while there was no significant difference between Calpain inhibitor I group and control group in the calosum, the diencephalon-mesencephalon and the pons-oblongata(P>0.05). Conclusion Calpain inhibitor I can decrease reactive changes of NDAI after injury and prevent mild NDAI from secondary axotomy.