Science · 1991 · 357 citations · 31 references
Life SciencesNeurobiologyNeuroscienceCellular NeurobiologyMolecular NeuroscienceSynaptic PlasticityCerebellar PhysiologyGlutamatergic SignalingLong-term DepressionNeurotransmissionSynaptic Strength RegulationSynaptic TransmissionCerebellar Long-term DepressionCerebellar Purkinje CellsClimbing FibersMetabotropic ReceptorsParallel Fiber-purkinje Cell Long-term DepressionPostsynaptic CurrentsPostsynaptic Long-term DepressionProtein Kinase Inhibitors
Long-term depression (LTD) in the intact cerebellum is a decrease in the efficacy of the parallel fiber-Purkinje neuron synapse induced by coactivation of climbing fiber and parallel fiber inputs. In cultured Purkinje neurons, a similar depression can be induced by iontophoretic glutamate pulses and Purkinje neuron depolarization. This form of LTD is expressed as a depression of alpha-amino-3-hydroxy-5-methyl-4- isoxazole-propionic acid (AMPA)-mediated current, and its induction is dependent on activation of metabotropic quisqualate receptors. The effect of inhibitors of protein kinase C (PKC) on LTD induction was studied. Inhibitors of PKC blocked LTD induction, while phorbol-12,13-diacetate (PDA), a PKC activator, mimicked LTD. These results suggest that PKC activation is necessary for the induction of cerebellar LTD.
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