中文摘要：

探讨核糖体S6激酶（ribosomal S6 kinase，RSK）Ser221（PDK1磷酸化位点）和Thr359／Ser363（ERK1／2磷酸化位点）的磷酸化水平以及总RSK蛋白表达量在小鼠脑低氧预适应发生发展过程中的变化。将成年雄性BALB／c小鼠（18-22g）随机分为正常对照（H0）和重复性低氧1-4次（H1-H4）等5组（每组n=6）。应用蛋白凝胶电泳（SDS-PAGE）和蛋白印迹（Western blot）技术，定量检测整体低氧预适应小鼠海马和皮层组织内Ser221位点（p-Ser221 RSK）和Thr359／Ser363位点（p-Thr359／Ser363RSK）的磷酸化水平以及总RSK蛋白表达量。结果表明，随着低氧暴露次数增加，小鼠海马和皮层组织内p-Ser221RSK磷酸化的水平显著增高（P〈0．05，n=6），伴随着p-Thr359／Ser363RSK磷酸化的水平明显降低（P〈0．05，n=6）；而RSK总蛋白的表达量则无明显改变。结果提示，Ser221RSK磷酸化水平增高和Thr359／Ser363RSK磷酸化水平降低可能参与了小鼠脑低氧预适应的发生发展过程。

英文摘要：

To investigate the changes of protein expression and phosphorylation levels at Ser221 （PDK1 site） and Thr359/Ser363 （ERK1/2 sites） of ribosomal S6 kinase （RSK） in the brain of hypoxie preconditioned mice, adult male BALB/e mice （weighing 18 - 22g） were randomly divided into 5 groups （ at least n =6 for each group） as follows： normoxie control （H0） and repetitive hypoxie exposure groups （ H1 - H4）, respectively. The biochemical techniques of SDS-PAGE and Western blot were performed to detect the total RSK protein expression, and phosphorylation levels at Ser 221 （p-Ser221 RSK） and Thr359/Ser363 sites （p-Thr359/Ser363 RSK） of RSK both in hippocampus and cortex of mice. We found that the increased p-Ser221 RSK （ P 〈 0.05, n = 6 ） eompanied with significant decrease of p-Thr359/Ser363 RSK levels （P 〈0.05, n = 6） both in hippocampus and cortex of hypoxie preconditioned mice. However, there were no significant changes of total RSK protein expression in the brain of mice following repetitive hypoxie exposure （ H1 - H4, n = 6 for each group） comparing with that of H0 group. These results suggest that the increased p-Ser221 RSK and the down-regnlated p-Thr359/Ser363 RSK might be involved in the development of cerebral hypoxie preconditioning of mice.