Extracellular calcium depletion in synaptic transmission.
Regulation of Ca2+ homeostasis in the extracellular space plays an important role in neuronal function. Several modeling studies and recent measurements have demonstrated that modest action potential or synaptic activity can result in a significant reduction in extracellular calcium ([Ca]o(2+)). Changes in [Ca]o(2+) can regulate intracellular signaling enzymes, such as Ca2+/calmodulin-dependent protein kinase II, and influence neuronal function at synaptic and nonsynaptic sites. The change in [Ca]o(2+) can affect several types of ion channels and neurotransmitter receptors and activate a Ca(2+)-sensitive receptor in neuronal membranes. Depletion of [Ca]o(2+) may function as an activity-dependent extracellular messenger that regulates nervous system function during development, learning, and disease.
Cohen
Jonathan E
JE
National Institutes of Health, National Institute for Child and Human Development, Section on Nervous System Development and Plasticity, Bethesda, MD 20892, USA.
Fields
R Douglas
RD
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D045604:Extracellular Fluid / Q000378:metabolism*; D006801:Humans; D043562:Receptors, G-Protein-Coupled / Q000737:chemistry / Q000378:metabolism; D009435:Synaptic Transmission / Q000502:physiology*
D043562:Receptors, G-Protein-Coupled; D002118:Calcium