胰岛素对大鼠脊髓损伤后HSP70、NOS表达的影响及抗凋亡作用

Effect of insulin on expression of HSP70,NOS and role of anti-apoptotic in spinal cord injury of rats

[目的]评估胰岛素对SD大鼠急性脊髓损伤的保护作用,并通过分析热休克蛋白70(HSP70)和一氧化氮合酶(NOS)在损伤脊髓组织中的表达情况来说明胰岛素保护作用的部分机理。[方法]将45只成年SD大鼠随机分为3组:A组(正常对照组,5只)、B组(损伤对照组,生理盐水治疗组,20只)、C组(实验组,胰岛素治疗组,20只)。将B、C组的实验大鼠分别在T9—T11处建立Allen’s重物坠落脊髓打击模型,并按所在组的要求给予不同的治疗。同时在损伤后12 h、1 d、3 d、7 d 4个时间点取材,每次5只,观测脊髓组织中HSP70和NOS的表达情况,以及损伤脊髓组织神经纤维细胞的凋亡情况。[结果]将A组和C组分别与B组比较,凋亡指数的差异均具有显著性意义(P<0.01)。HSP70表达,A组与B组比较,差异具有显著性意义(P<0.01);C组与B组比较,差异具有显著性意义(12 h,P<0.05;1 d、3 d、7 d,P<0.01)。NOS表达,A组与B组比较,差异具有显著性意义(P<0.01);而C组与B组比较,差异无显著性意义(P>0.05)。[结论]胰岛素对损伤脊髓组织具有明显的保护作用,这些作用可能是通过增加HSP70表达和抑制NOS表达来实现的。

[ Objective] To research the protective effect of insulin on the acute injured spinal cord in rats by the analysis of the heat shock protein 70 （HSP70） and nitric oxide synthase （NOS） in the injured spinal cord tissues. [ Methods] Forty -five SD rats were randomly divided into three groups： group A （control group, 5 rats） ;group B （blank group, normal saline treatment group, 20 rats） ;group C （the insulin treatment group, 20 rats）. The rats in the groups B and C were established the spinal cord model of Allen~ heavy hit in 39 -11. Every group of the three was given different treatment, and the content of I-ISP70 and NOS in the injury spinal cord tissues was recorded at the 12 h, 24 h, 3 d and 7 d points after injury, every time 5 rats. [ Results ] Group A and group C were compared with group B group separately, the difference in apoptosis index were significant （P 〈0.01 ）. In the expression of HSP70： the difference between group A and group B was significant （P 〈0. O1 ） ; the difference between group C and group B was also significant （ 12 h, P 〈0.05 ; 1 d, 3 d and 7 d, P 〈0.01 ）. In the expression of NOS： the difference between group A and group B is significant （P 〈0.01 ） ; while the difference between group C and group B was non -significant （P 〉 0. 05）. [ Concision ] Insuhn show a significant protective effect on the injured spinal cord, which may promote expression of HSP70 and inhibit to expression of NOS.