Do calcium channel classifications account for neuronal calcium channel diversity

Abstract Calcium (Ca 2+ ) ions are involved in the development and control of a variety of neuronal properties and functions such as channel expression, synaptic transmission and neurosecretion. The main pathway by which Ca 2+ enters the intracellular space is through voltage-activated Ca 2+ channels that can be classified according to their different biophysical and pharmacological properties. Identification and characterization of these channel types are prerequisites for understanding the mechanisms that underlie Ca 2+ -controlled processes. In this article we summarize the efforts made to identify neuronal Ca 2+ channel types, and we attempt to evaluate how useful existing classifications are in assigning specific properties and functions to distinct channel types in neurons.