What is "polydendrocytes"

Polydendrocytes (also known as NG2 cells, NG2 glia, or oligodendrocyte progenitor cells) are process-bearing glial cells ( neuroglia) in the mammalian central nervous system (CNS) that are identified by the expression of the NG2 chondroitin sulfate proteoglycan ( CSPG4) and the alpha receptor for platelet-derived growth factor ( PDGFRA). They are distinct from other cell populations such as neurons, astrocytes, oligodendrocytes, microglia, and neural stem cells and are recognized as the fourth major glial cell type in the mammalian CNS. Studies have implicated polydendrocytes in many cellular and physiological processes. Polydendrocytes in the postnatal mouse CNS and those grown in culture generate oligodendrocytes, and thus they are often equated with oligodendrocyte progenitor cells (OPCs). Under some culture conditions, polydendrocytes give rise to astrocytes. A subpopulation of polydendrocytes in the gray matter of the embryonic CNS also generates protoplasmic astrocytes. In addition, polydendrocytes express receptors for various neurotransmitters and undergo membrane depolarization when they receive synaptic inputs from neurons.