Activation of pre- and postsynaptic protein kinase C during tetraethylammonium-induced long-term potentiation in the CA1 field of the hippocampus

• Published in: Neuroscience letters 2000-05, Vol.286 (1), p.53-56
• Main Authors: Ramakers, Geert M.J., Pasinelli, Piera, van Beest, Moniek, van der Slot, Annemarie, Gispen, Willem-Hendrik, De Graan, Pierre N.E.
• Format: Article
• Language: English
• Subjects: 2-Amino-5-phosphonovalerate - pharmacology; 4-Aminopyridine - pharmacology; Animals; Biological and medical sciences; Ca 2+ channel; Calcium Channel Blockers - pharmacology; Calmodulin-Binding Proteins - metabolism; Central nervous system; Electrophysiology; Excitatory Amino Acid Antagonists - pharmacology; Excitatory Postsynaptic Potentials - drug effects; Excitatory Postsynaptic Potentials - physiology; Fundamental and applied biological sciences. Psychology; GAP-43 Protein - metabolism; GAP-43/B-50; Hippocampus - cytology; Hippocampus - drug effects; Hippocampus - metabolism; In Vitro Techniques; K + channel; Long-term potentiation; Long-Term Potentiation - drug effects; Long-Term Potentiation - physiology; Nerve Tissue Proteins - metabolism; Neurogranin; Nifedipine - pharmacology; Phosphorylation; Potassium Channel Blockers; Potassium Channels - drug effects; Potassium Channels - metabolism; Presynaptic Terminals - drug effects; Presynaptic Terminals - metabolism; Presynaptic Terminals - ultrastructure; Protein kinase C; Protein Kinase C - drug effects; Protein Kinase C - metabolism; Rats; RC3; Signal Transduction - drug effects; Signal Transduction - physiology; Synaptic Membranes - drug effects; Synaptic Membranes - metabolism; Synaptic Membranes - ultrastructure; Synaptic Transmission - drug effects; Synaptic Transmission - physiology; Tetraethylammonium - pharmacology; Vertebrates: nervous system and sense organs
• ISSN: 0304-3940; 1872-7972
• DOI: 10.1016/S0304-3940(00)01081-8

Tetraethylammonium (TEA) induces a form of long-term potentiation (LTP) that is independent on N-methyl- d-aspartate (NMDA) receptor activation (LTP K). LTP K may be a suitable chemical model to study molecular mechanisms underlying LTP. We monitored the phosphorylation state of two identified neural-specific protein kinase C (PKC) substrates (the presynaptic protein GAP-43/B-50 and postsynaptic protein RC3) after different chemical depolarisations. TEA induced a long-lasting increase in synaptic efficacy in the CA1 field of the hippocampus and increased the phosphorylation of both GAP-43/B-50 and RC3 (51 and 56.1%, respectively). These effects were blocked by the voltage-dependent calcium channel antagonist nifedipine, but not by the NMDA receptor antagonist AP5. These data show that in LTP K the in situ phosphorylation of pre-and postsynaptic PKC substrates is increased, indicating that NMDA receptor-dependent and NMDA receptor-independent LTP share common Ca 2+-dependent expression mechanisms, including activation of pre- and postsynaptic PKC.