5-HT1A receptors transactivate the platelet-derived growth factor receptor type beta in neuronal cells

► 5-HT and 5-CT can transactivate PDGFRβ in the absence of PDGF ligand. ► 5-HT, but not 5-CT, increases ERK1/2 phosphorylation in a PDGFRβ-independent manner. ► PDGFRβ transactivation was observed in SH-SY5Y cells and primary cortical neurons. ► PDGFRβ transactivation is PLC, calcium, and Src kinase dependent. ► PDGFRβ transactivation is pertussis toxin sensitive.