Transtentorial cerebellar c-jun expression after focal cerebral cortical injury in mice

Delayed and remote effect of focal cerebral cortical lesion on cerebellum r emains unclear. The c-Jun, an inducible transcription factor of cellular im mediate early gene, is the predominant transcription factor and consistent marker for neurons that respond to stress or injury. We use a mouse cryogen ic injury model to study the spatial and temporal changes of c-jun in the c erebellum after focal neocortical lesion. A transient and moderate expressi on of c-jun mRNA was found in the cerebellum with central dominance since 3 day postinjury a nd gradually subsided with in 2 weeks. A distinct increme nt of c-Jun protein expression in Purkinje cells of the bilateral cerebella r hemispheres with focal connotation in the vermis was detected since 1 wee k postinjury. These findings suggest that the delayed and remote c-jun expr ession of the cerebellum, functionally connected with the cerebral cortex, indicate transneuronal gene activation. (C) 2000 Elsevier Science Ireland L td. All rights reserved.