Receptor expression in primary cultures of neurons or astrocytes.

beta-Adrenergic receptors are abundant on astrocytes which contain mainly the beta 1 subtype. These cells also possess alpha 1 and alpha 2 receptors. Neurons display fewer beta-adrenergic receptor sites and those present are of the beta 2 subtype. Dopaminergic receptors are found on astrocytes and show a regional variation. Serotonergic receptors have been demonstrated on astrocytes but are expressed to a larger extent in neurons. Astrocytes display muscarinic receptors but have no receptor sites for the transmitter amino acids glutamate and GABA. GABA receptors are present on cerebellar granule cells, are induced by the presence of GABA agonists in the medium and mediate an evoked release of glutamate. Glutamate receptors are found on cultured cortical interneurons. Some, but not all, peptide hormones have receptors on astrocytes and/or neurons in primary cultures.