[3H]spiperone binding sites in rat primary glial cultures, C6 glioma, and B104 neuroblastoma

Binding sites for [3H]spiperone were detected on membranes from primary glial cultures from neonatal rat cortex and striatum and from the C6 glioma cells. [3H]Spiperone binding was displaceable by d-butaclamol. However, competition studies suggest that [3H]spiperone binding to primary glial cultures was mainly to serotonergic sites, and binding to the C6 glioma was alpha-adrenergic. No specific binding was detected to membranes from B104 neuroblastoma cells. Although [3H]spiperone binding to glial sites on whole striatum under generally used conditions is small (about 10%), the striatal glial hyperactivity that is often associated with neuronal degeneration could lead to an overestimation of presumed neuronal binding sites for dopaminergic ligands.