Histamine and prostanoid receptors on glial cells.

Glial cells in vitro express at least two types (H1 and H2) of histamine receptors and three types (EP, FP, and TP) of prostanoid receptors. The receptors expressed by glial cells differ according to the cell type and source in the brain. Furthermore primary astrocytes of same type derived from the same brain region are composed of heterogeneous subpopulations expressing different subsets of receptors. Fura-2 based Ca2+ microscopy revealed that astrocyte processes are important sites for histamine-induced Ca2+ signalling. Histamine and prostanoid receptors on glial cells may play important roles in the actions of histamine and prostanoids in the central nervous system.