Regulation of calcium in the cerebellum

Abstract

Ca2+ is an important ion in CNS biology, where if plays a critical role in basic functions of neurons, glia and other cell types. In CNS neurons, Ca 2+ is a participant in the generation of electrical signals, an inducer and regulator of synaptic transmission, and a second messenger that controls many biochemical processes. Ca 2+ is also a signal transmitter and second messenger in glial cells. Ca 2+ levels in neurons and glia are dynamic but judiciously controlled in order to maintain biological processes at a level compatible with life. An excess or defi cit of Ca 2+ can result in cell damage or death. A variety of cellular mechanisms contribute to or enable the changes in intracellular Ca 2+, referred to as Ca 2+ signaling, that are essential for normal cell function, some of which are present in all cells and others that are unique to a particular class of cells. This chapter will briefl y describe the cellular mechanisms that contribute to Ca 2+ signaling in cerebellar and other CNS neurons. These mechanisms are located at presynaptic sites (e.g., axon terminals), where they regulate transmitter release, and/or at postsynaptic sites (e.g., dendrites), where they infl uence synaptic responses and other physiological functions.