Figure 7.

GSK-3β shows increased activation and hyperphosphorylates τ at 0–6 h after heat shock. (A) Immunoblot of cerebral extracts from control (C) and heat-shocked rats probed with antibodies against inactivated GSK-3β [(phospho-GSK-3β (Ser⁹)] (arrow) and Cdk5 as a loading control (lower row). Note the decrease in the inactivated form of GSK-3β after heat shock. (B–D) Immunoblot probed with the activation-independent antibody against GSK-3β (B) and autoradiograph (C) of Coomassie blue-stained (D) SDS/PAGE gels of aliquots of kinase assay mixtures show hyperphosphorylation of τ at 0–6 h. Note the equal amounts of GSK-3β (B) and τ (D) in all lanes.