Expression of cyclin-dependent kinase 5 in cerebral cortex after subarachnoid hemorrhage in rats / 国际脑血管病杂志

ABSTRACT

Objective To investigate the expression and cellular localization of cyclin-dependent kinase 5 (Cdk5) in cerebral cortex after subarachnoid hemorrhage (SAH) in rats.Methods Fifty-two male Sprague Dawley (SD) rats were randomly divided into either a sham operation group (n =12) or a SAH group (n =40).The latter was randomly redivided into 6,12,24 h,and day 2 and 3 subgroups (n =8 in each group).A rat SAH model was induced by injecting fresh blood into the prechiasmatic cistern.Western blot and immunohistochemistry were used to detect the expression of Cdk5 in rat brain cortex.Double labeling immunofluorescence staining was used to detect the cellular localization of Cdk5 protein in cerebral cortex.Neuronal nuclear antigen labeled neurons,and glial fibrillary acidic protein labeled astrocytes.Results Western blot showed that the expression of Cdk5 protein was up-regulated at 12 hours after SAH (t =3.709,P =0.001),and it reached the peak on day 1 (t =3.475,P=0.002).Immunohistochemistry showed that the proportion of Cdk5 positive cell was also increased gradually after SAH,and the changes of time course were consistent with the results of Western blot,and it reached the peak on day 1 (t =4.320,P =0.000).Double labeling immunofluorescence showed that Cdk5 was mainly expressed in the neuronal cytoplasm in the sham operation group,and Cdk5 shifted to the neuronal nuclei in the SAH group.Cdk5 was mainly colocalized between astrocytes and neurons.Conclusions SAH up-regulates the expression of Cdk5 protein in cerebral cortex.Cdk5 may be involved in early brain injury after SAH.