Short-term plasticity of small synaptic vesicle (SSV) and large dense-core vesicle (LDCV) exocytosis.
Synaptic plasticity results from changes in the strength of synaptic transmission upon repetitive stimulation. The amount of neurotransmitter released from presynaptic terminals can regulate short-term plasticity that lasts for a few minutes. This review focuses on short-term plasticity of small synaptic vesicle (SSV) and large dense-core vesicle (LDCV) exocytosis. Whereas SSVs contain classical neurotransmitters and activate ion channels, LDCVs contain neuropeptides and hormones which primarily activate G protein-coupled receptors (GPCRs). Thus, LDCV exocytosis is mainly associated with modulation of synaptic activity and cannot induce synaptic activity by itself. As in SSV exocytosis, repetitive stimulation leads to short-term enhancement of LDCV exocytosis: i.e., activity-dependent potentiation (ADP) which represents potentiation of neurotransmitter release. Short-term plasticity of SSV exocytosis results from Ca2+ accumulation, but ADP of LDCV exocytosis does not. Here, we review the signaling mechanisms and differences of short-term plasticity in exocytotic processes of SSV and LDCV.
Park
Yongsoo
Y
Department of Life Science, Pohang University of Science and Technology, Pohang 790-784, Republic of Korea.
Kim
Kyong-Tai
KT
D002118:Calcium / Q000378:metabolism; D005089:Exocytosis; D007473:Ion Channels / Q000378:metabolism; D009473:Neuronal Plasticity / Q000502:physiology*; D018377:Neurotransmitter Agents / Q000378:metabolism; D011494:Protein Kinases / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism; D022142:Secretory Vesicles / Q000502:physiology*; D013572:Synaptic Vesicles / Q000502:physiology*
D007473:Ion Channels; D018377:Neurotransmitter Agents; D043562:Receptors, G-Protein-Coupled; D011494:Protein Kinases; D002118:Calcium