RECEPTOR-ACTIVATED CA2+ INFLUX - HOW MANY MECHANISMS FOR HOW MANY CHANNELS

Receptors that are coupled to the production of inositol (1,4,5)-trisphosphate cause an increase in cytosolic free Ca2+ concentration as a consequence of both Ca2+ mobilization from intracellular stores and Ca2+ influx through the plasma membrane. Although this latter phenomenon appears attributable to the activation of a number of Ca2+-permeable channels, the channels that are controlled by the Ca2+ content of the intracellular stores have recently received much attention. In this review, Cristina Fasolato, Barbara Innocenti and Tullio Pozzan summarize the characteristics of this Ca2+-influx pathway and discuss the hypotheses about its mechanism of activation and its relationship with other receptor-activated Ca2+ channels.