Differential staining of glia and neurons by modified Golgi-Cox method

Golgi-Cox staining has been extensively used in neuroanatomical studies. Despite its unique property to impregnate and show neuronal and glial morphology, its capricious nature, less consistency and long staining time constrain users to use it as first choice. Here we report a modification of the Golgi-Cox method to reliably and differentially stain neurons and glia in the rat brain within 48 h. In summary, exposure (at any stage) of the brain or the tissue sample to be stained to a fixative [4% paraformaldehyde (PF) or 4% formaldehyde] dramatically increased the number of stained glia; whereas if the tissues were not treated with a fixative, neurons were stained. To our knowledge this is the first report of differential staining of glia and neurons using Golgi-Cox method; however, mechanism is unclear.

► We describe a simple modification of the Golgi-Cox method to differentially stain neurons and glia.
► If the rat brain or brain tissue block was exposed to a fixative at any stage, glial cells were stained, whereas in its absence neurons were stained.
► Same brain (different portions) may be used for differential staining of neurons and glia.
► Staining was achieved in less than 48 h; incubation temperature of 37 °C was critical.