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Flashcards in LTD Deck (4)
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What are the two types of long term depression

Depotentiation - removal of previous potentiation
LTD de novo - No previous potentiation


What is the Albus Marr model

Climbing fibre input indicates a motor error and weakens the parallel fibre to purkinje cell synapse


What is the mechanism of LTD in the cerebellum

Doesn't involve NMDA receptors
Depolarization of the climbing fibre - Ca influx at pre synapse - Causes increased glutamate release
glutamate acts on AMPA receptors at the postsynaptic neuron - increased Na influx postsynaptically
Also acts on GPC metabotropic glutamate receptor - activates phospholipase C - IP3 DAGS - DAGS activates PKC - phosphorylates GluR2 AMPA receptor - Both mechanisms required in order for LTD to occur


What is the process of hippocampal LTD

Low EPSP causes only partial unblocking of magnesium from NMDA receptors - Only partial binding of glutamate so only partial influx of calcium - Small calcium influx activates more phosphatase action over kinase - dephosphorylation of AMPA receptors reduces activity and endocytosis of AMPA receptors - reducing synapses connection - LTD - can reduce previously potentiated synapse