Calcium-binding protein parvalbumin as a neuronal marker.

Abstract

Ca2+ ions, involved in the control of many important physiological functions, require the presence of specific intracellular Ca2+-binding proteins to exert their regulatory roles. Many of the latter have been extracted and purified. Thus, troponin-C regulates muscle contraction1 and calmodulin is involved in a variety of fundamental cellular activities2,3. Parvalbumin seems to be restricted to muscle and brain4–6 but its physiological role is not yet clear. In muscle it probably participates in a regulatory system operating mainly in fast contracting muscles7,8, but in brain, even its anatomical distribution is unknown. We now describe the localization by immunohistological means of parvalbumin in neurones scattered throughout the central nervous system of the rat. Although the distributions of parvalbumin- and GABAergic neurones are similar, the physiological function of parvalbumin-immunoreactive neurones is not yet recognizable.