PSY492H1 Lecture Notes - Lecture 6: Kinesin, Long-Term Memory, Synaptic Tagging
Document Summary
Similar to memories, ltp exhibits two forms: short-term (s-ltp) and a long-term form (l-ltp) Strong high frequency stimulation (hfs) produces l-ltp. Protein synthesis inhibitors applied during induction of ltp prevents l-ltp but not s-ltp. Recall: this hypothesis said that short-term memory only requires translation of existing mrna while long- term memory requires synthesis of new proteins produced my new mrna products generated from genomic cascades. In the synapse-to-nucleus model the stimulation of a postsynaptic neuron activates second messengers that then activate protein kinases. Second messengers or their kinase targets translocate into the nucleus where they phosphorylate creb and transcription is initiated. The ws initiates molecular processes at the synapse but does not induce action potentials (ap) at soma (i. e. only s-ltp). Next, this ws is followed by an electrical stimulation applied to the axon (called antidromic stimulation) of the postsynaptic neuron to produce action potentials in those neurons. This stimulation allows the influx of ca2+ into the soma and nucleus.
