他可莫司对丙烯酰胺中毒大鼠热休克蛋白70及Bcl-2和Bax蛋白表达的影响

目的 探讨他可莫(tacrolimus,FKS06)对丙烯酰胺(acrylamide,ACR)中毒大鼠行为学和热休克蛋白70(HSP70)及神经元凋亡相关蛋白Bcl-2和Bax表达的影响.方法 40只Wistar雄性大鼠随机分成4组:正常对照组(生理盐水)、模型组(30mg/kgACR)、FK506低剂量组(30mg/kg ACR+0.5mg,kgFK506)和高剂量组(30ms/kg ACR+1.0ms/ksFK506).各组给药5次/周,持续4周,每周进行步态评分;第28天后用蛋白免疫印迹法(Western bloting)方法检测HSP70及Bci-2、Bax蛋白表达水平的变化.结果 与模型组相比,FK506低、高剂量组大鼠步态评分分值分别降低了30.1%和47.7%,差异有统计学意义(P<0.01).与模型组相比,FK506低、高剂量组除脊髓中HSP70表达不明显.大脑和坐骨神经中HSP70表达分别增加了11.6%、33.3%和56.3%、58.5%,差异有统计学意义(p<0.05或P<0.01);与模型组比较,FKS06低剂量组的大脑、脊髓中Bcl-2蛋白表达变化均不明显,坐骨神经中Bcl-2蛋白表达增加了39.1%,差异有统计学意义(P<0.01);FK506高剂量组Bcl-2蛋白表达在大脑、脊髓和坐骨神经中分别升高了16.3%、14.8%和56.0%,差异有统计学意义(P<0.01),与模型组比,FK506低剂量组脊髓中Bax蛋白表达降低46.8%,FK506高剂量组大脑和脊髓中分别降低了16.4%和40.2%,差异均有统计学意义(P<0.01);FKS06低、高剂量组在大脑、脊髓和坐骨神经组织中Bcl-2/Bax比值分别升高了15.9%、33.3%、36.9%和30.1%、49.1%、60.1%,差异均有统计学意义(P<0.01).结论 FK506对丙烯酰胺中毒大鼠神经损伤有保护作用,HSP70、Bcl-2表达上调,Bax表达下调可能是其保护机制之一.

Effects of tacrolimus (FK506)on heat-shock proteins 70,Bcl-2 and Bax expression in nervous tissue of acrylamide-induced rat

Objective To investigate the effects of tacrolimus(FK506)on behavioral function and heat-shock Droteins(HSP70)expression in nervous tissues of acrylamide(ACR)-induced rats.Methods To-tally40 health wistar rats were randomly divided into control group,model group,low and high doses of FK506 groups.All four groups were treated five times per week for four weeks.Gait score was measured every week.And rats were sacficed on day 28,the cerebrum,spinal cord and sciatic nerve were dissected,and homoge-nized in ice bath,then the levels of HSP70 and Bcl-2,Bax were analyzed by westem bloting.Results Com-Dared with the ACR model group,the gait score in low and high doses of FK506 groups decreased by 3.1% and 47.7%resDectively in the 4th week.In the cerebrum and sciatic nerve pellet,the level of HSP70 in the FK506 groups increased by 11.6%,33.3%and 56.3%,58.5%(P<0.01),but no significant changes existed in spinal cord.The ievel of Bcl-2 in the sciatic nerve pellet incmased by 39.1%(P<0.01)but no significant changes ex-isted in the cerebrum and spinal cord from low dose of FK506 group.And the level of Bax in the spinal cord pellet markedly increased by 46.8%but not in cerebrum and sciatic nerve pellet;Whereas in the tissues men-ioned above,the levels of Bcl-2 were enhanced remarkably by 16.3%,14.8%and 56.0%(P<0.01)in the high dose of FK506 group.And the level of Bax in the cerebrum and spinal cord pellet markedly increased by 16.4%and 40.2%but not in sciatic nerve.The values of Bcl-2/Bax in low and high doses of FK506 groups clearly in-creased bv 15.9%,33.3%,36.9%and 30.1%,49.1%,60.1%(P<0.01).Conclusion The administration of FK506 has dramatically neuroprotective effects against the development of ACR neuropathy,which may be re-lated to up-regulating the expression of HSP70 and Bcl-2 with down-regulating the expressmn of Bax.