Propidium iodide staining: A new application in fluorescence microscopy for analysis of cytoarchitecture in adult and developing rodent brain

► Propidium iodide (PI) provides cytoarchitectural details in fluorescence microscopy. ► PI staining led to similar staining patterns as hemalaun in bright field microscopy. ► Common markers incompletely visualize the cell organization in the developing CNS. ► PI staining is a crucial implement in fluorescence analysis of postnatal tissues.