Lysophosphatidic acid-induced calcium signals in cultured rat oligodendrocytes

OLIGODENDROCYTES are the myelin forming glial cells of the CNS and are know n to express receptors linked to ion channels and intracellular second mess enger cascades. In this paper, we describe the intracellular calcium respon ses df cells from the oligodendrocyte lineage to application of lysophospha tidic acid (LPA), a naturally occurring, growth factor-like phospholipid. O ligodendrocyte precursors did not respond to application of LPA (1 mu M). I n mature oligodendrocytes, however, LPA (1 mu M) induced an increase in the intracellular calcium concentration ([Ca2+](i)). In the majority-of cells this increase was followed by a persistent:plateau phase. The LPA-induced [ Ca2+](i) signal vanished in Ca2+-free medium, implying that it arose,due to a Ca2+ influx across the plasma membrane. Preincubation of the cells with Pertussis-toxin prevented the generation of LPA-induced [Ca2+](i) signals. We conclude that cultured rat oligodendrocytes express functional LPA recep tors, which mediate a transmembrane Ca2+ influx via a Pertussis-toxin-sensi tive G-protein. (C) 1999 Lippincott Williams & Wilkins.