RESUMO
BACKGROUND: Golgi-Cox staining is a powerful histochemical approach which has been used extensively to visualize the morphology of neurons and glia. However, its usage as a first-choice method is hindered by its uncertain nature, diminished consistency and lengthy staining duration. The FD Rapid GolgiStain™ Kit (FD Neurotechnologies, Inc., USA) has been developed by employing the Golgi-Cox approach. It is a simple, reliable and reproducible way of performing Golgi impregnation for the analysis of neuronal morphology. NEW METHOD: We report here simple modifications to the manufacturer's protocol which enable reproducible and reliable staining of glial cells. RESULTS: Exposure of brain tissue to 4% paraformaldehyde (PFA) during perfusion followed by postfixation with 8% glutaraldehyde in 4% PFA led to only glial cells being stained, whereas in the absence of postfixation both neurons and glia were stained with unclear morphology. Additionally, we found that impregnation at 26°C±1 was critical to attain uniform staining. COMPARISON WITH EXISTING METHOD: Our modified Golgi-Cox approach is consistent and reproducible and affords uniform glial staining throughout the brain. CONCLUSION: As this protocol stains only a small percentage of cells, it is suitable for the analysis of individual cells.