大鼠脑缺血后神经元中PYK2及 p38MAPK的活化及其意义

目的观察大鼠局部脑缺血后缺血区神经元中PYK2及p38MAPK的表达并探讨其意义。方法建立大鼠局部脑缺血模型，在缺血后15、30和60min时处死大鼠，采用免疫组化方法观察大鼠缺血区神经元中PYK2及p38MAPK的表达变化。结果正常大鼠皮层仅有微量活化型PYK2和活化型p38MAPK表达。缺血15min后，皮层神经元可见活化型PYK2强免疫阳性标记，这些有活化型PYK2表达的神经元亦呈p38MAPK免疫阳性。缺血区神经元中活化型PYK2和活化型p38MAPK免疫标记在缺血30min时达到最强，60min时开始减退。结论缺血可以诱发神经元中PYK2活化，既而通过p38MAPK信号转导通路介导神经元对缺血的应急反应。

Phosphorylation of PYK2 and p38MAPK in neurons after focal cerebral ischemia in rats

Objective To investigate and evaluate the changes of phospho PYK2 and phospho p38MAPK expression in neurons after focal cerebral ischemia. Methods Focal ischemia reperfusion model was established in rats, and by using immunostaining, the changes of phospho PYK2 and phospho p38MAPK expression in neurons was observed. Results Faint phospho PYK2 and phospho p38MAPK immunoreactivity were revealed in normal cortical neurons. Fifteen minutes after the ischemia onset, a pronounced upregulation of phospho PYK2 and phospho p38MAPK immunoreactivities were evident in these ischemia attacked neurons. The immunoreactivities of phospho PYK2 and phospho p38MAPK reached its peak at 30min after ischemia, and decreased 60min after ischemia. Conclusion Cerebral ischemia was able to induce neuronal PYK2 phosphorylation. The activation of PYK2 might link ischemia attack to the p38MAPK signaling pathway to initiate the neuronal response to the stress stimuli