kn-92 and staurosporine-aglycone

In this study, contributions of intracellular regulatory cascades in the induction of S100B expression in rat hippocampal CA1 area during long term posttetanic potentiation (LTP) were estimated. The activation of transcription factor p53 (positive regulator of S100B transcription) by nutlin-3 increased the basal content of S100B mRNA up to 151% of the control level, which was significantly lower than its content in tetanized slices (280%). Therefore, p53 seems to be not unique transcription factor upregulating S100B expression during LTP. The inhibitor of Ca2+/calmodulin-dependent kinases (CaMKs) KN-93 fully blocked the increase of S100B mRNA after tetanization, while KN-92 (inactive analogue of KN-93) was ineffective. The inhibitor of CaMKII and receptor tyrosine kinases K-252a essentially suppressed S100B expression during LTP, the inhibition of MAPK p38 or RSK2 moderately decreased, and the inhibition of MEK1 did not influence S100B mRNA content. Thus, CaMKs play a key role in the induction of S100B expression during LTP.

Topics: Action Potentials; Animals; Benzylamines; CA1 Region, Hippocampal; Calcium-Calmodulin-Dependent Protein Kinase Type 2; Carbazoles; Gene Expression Regulation; Imidazoles; Indole Alkaloids; Long-Term Potentiation; Male; MAP Kinase Kinase 1; p38 Mitogen-Activated Protein Kinases; Piperazines; Rats; Rats, Wistar; Receptor Protein-Tyrosine Kinases; Ribosomal Protein S6 Kinases, 90-kDa; RNA, Messenger; S100 Calcium Binding Protein beta Subunit; Sulfonamides; Synaptic Transmission; Tissue Culture Techniques; Tumor Suppressor Protein p53