钙敏感受体抑制剂对创伤性颅脑损伤大鼠神经元凋亡的作用研究

Effect of calcium sensitive receptor inhibitors on neuronal apoptosis in rats with traumatic craniocerebral injury

目的 探索钙敏感受体抑制剂在创伤性颅脑损伤大鼠模型中对神经元凋亡的影响。方法 采用皮层定位精度撞击器进行大鼠的TBI造模;将大鼠随机分为对照组,TBI+溶剂组和TBI+钙敏感受体拮抗剂(NPS2390)组。通过mNSS对大鼠的神经功能进行评分;在TBI后24小时取脑,将全脑进行湿重与干重的称重,计算脑水肿程度;通过Western blot检测蛋白的表达水平。结果 TBI后溶剂组相比对照组,其脑水肿程度显著增加(80.03%vs 79.22%,P=0.018),神经功能评分显著下降(8.3vs 1.0,P=0.014),给予NPS2390后,可以降低TBI后脑水肿程度(79.38%vs 80.03%,P=0.029)及逆转神经功能评分下降(6.1vs 8.3,P=0.040)。TBI会导致神经元凋亡水平增加(55.3%vs 1.1%,P=0.006),cleaved caspase-3蛋白表达水平增加(2.71vs1.0,P=0.033),而NPS2390可以降低TBI神经元凋亡水平(30.2%vs 55.3%,P=0.031),相比TBI+溶剂组显著降低cleaved caspase-3的表达水平(1.52vs 2.71,P=0.041)。TBI还会降低抗凋亡蛋白Bcl-2的表达水平(0.42vs1.0,P=0.035),增加促凋亡蛋白Bax的表达水平(1.89vs 1.0,P=0.021),增加细胞色素C的释放到胞浆的水平(2.89vs 1.0,P=0.019),给予NPS2390后,与TBI+溶剂组相比,Bcl-2表达增加(0.65vs 0.42,P=0.042),Bax表达水平增加(1.22vs 1.89,P=0.033),释放到胞浆中的细胞色素C降低(1.41vs 2.89,P=0.022)。结论 通过NPS2390抑制钙敏感受体可以减轻大鼠TBI后的神经元凋亡,对TBI起到保护作用。

Objective To determine the role of calcium-sensing receptor(CaSR)inhibitor in neuronal apoptosis in TBI rats.Methods Using a controlled cortical impact model in rats,we divided rats into Sham,TBI+vehicle and TBI+CaSR inhibitor groups.mNSS was applied to detect the neurological function of rats.Brain edema was measured by weighing the wet and dry brain.Protein levels was administered by using Western blot.Results Compared with the sham group,the brain edema level in TBI+vehicle group significantly increased(80.03%vs 79.22%,P=0.018),as well as the mNSS(8.3 vs 1.0,P=0.014);while giving the antagonist NPS2390 could decrease the brain edema level(79.38%vs 80.03%,P=0.029)and rescue the damage of neurological function in mNSS(6.1 vs 8.3,P=0.040).TBI can also increase the neuronal apoptosis(55.3%vs 1.1%,P=0.006),while NPS2390 protect neurons from apoptosis(30.2%vs55.3%,P=0.031).In the expression of cleaved caspase-3,TBI increased its protein expression(1.52 vs 2.71,P=0.041);in the expression of Bcl-2 and Bax,TBI separately decreased and increased their expression to 0.42(0.42 vs 1.0,P=0.035)and 1.89(1.89 vs 1.0,P=0.021).In terms of TBI+NPS2390 group,the expression of the three proteins compared with TBI+vehicle group,changed to 1.52(1.52 vs 2.71,P=0.041),0.65(0.65 vs 0.42,P=0.042)and 1.22(1.22 vs 1.89,P=0.033)respectively.Conclusion Inhibiting the CaSR through NPS2390 can decreased the neuronal apoptosis and protect TBI.