SRC ACTIVATION IN THE INDUCTION OF LONG-TERM POTENTIATION IN CA1 HIPPOCAMPAL-NEURONS

Long-term potentiation (LTP) is an activity-dependent strengthening of synaptic efficacy that is considered to be a model of learning and me mory. Protein tyrosine phosphorylation is necessary io induce LTP. Her e, induction of LTP in CA1 pyramidal cells of rats was prevented by bl ocking the tyrosine kinase Src, and Src activity was increased by stim ulation producing LTP. Directly activating Sre in the postsynaptic neu ron enhanced excitatory synaptic responses, occluding LTP. Src-induced enhancement of alpha-amino-3-hydroxy-5-methylisoxazolepropionic acid (AMPA) receptor-mediated synaptic responses required raised intracellu lar Ca2+ and N-methyl-D-aspartate (NMDA) receptors. Thus, Sre activati on is necessary and sufficient for inducing LTP and may function by up -regulating NMDA receptors.