中文摘要：

目的探讨在增龄过程中SD大鼠髓核组织中HSC70的表达及其意义。方法 3月龄、12月龄、24月龄SD大鼠各8只,HE染色检测椎间盘组织的退变情况;RT-PCR法测定髓核组织中HSC70的表达;Western blot检测髓核组织中HSC70的表达。结果大鼠增龄过程可部分反映椎间盘的退变变化;RT-PCR和Western blot均显示HSC70在不同年龄组SD大鼠髓核中均有表达,且24月龄（1.26±0.21;0.56±0.07）表达较3月龄组（1.60±0.30;0.68±0.07）表达明显降低（P〈0.05;P〈0.01）;但与3月龄和24月龄组相比,12月龄组HSC70变化（1.49±0.29;0.61±0.09）无差异（P〉0.05;P〉0.05）。结论 HSC70在椎间盘退变过程中的表达降低,提示HSC70的降低可能与椎间盘退变的发展进程有关。

英文摘要：

Objective To investigate the expression and significance of HSC70 in nucleus pulposus of rats during the aging process.Methods The models of youth,middle-aged and old rat were made with the 3-month,12-month and 24-month SD rats respectively.The grades of intervertebral disc degeneration were measured with HE staining.The changes of HSC70 mRNA and protein expression in nucleus pulposus were measured by RT-PCR and western blot respectively.Results The aging process of rat partly reflected the process of intervertebral disc degeneration.There was expression of HSC70 in nucleus pulposus in every group and compared to 3 month group（1.60±0.30;0.68±0.07）,HSC70 mRNA and protein were expressed lower in 24 month group（1.26±0.21;0.56±0.07）（P0.05 and P0.01 respectively）.Conclusion Expressions of HSC70 are down-regulated in nucleus pulposus in older group.Down-regulation of HSC70 may relate to the process of the lumbar disc degeneration.