Calcium signaling and secretion in pituitary cells

An important trigger of hormone secretion from pituitary cells is a rise in cytosolic Ca2+ ([Ca2+](i)). Pituitary cells may modulate [Ca2+](i) by an increased membrane flux from the extracellular space and/or by a release from intracellular stores. Both mechanisms can support exocytosis, although in different pituitary cell types one or the other mechanism may predominate. Molecular events transducing a rise in [Ca2+](i) into hormone secretion are still poorly understood. Here, the exocytotic machinery in pituitary cells is briefly reviewed in terms of the spatial organization of [Ca2+](i) elevation relative to the Ca2+ sensor(s). (C) 1996, Elsevier Science Inc.