Appraisal of the effect of brain impregnation duration on neuronal staining and morphology in a modified Golgi-Cox method

Background: Golgi-Cox staining method is considered as one of the best neurohistological and fascinating staining techniques to reveal the cytoarchitecture of the brain. Requirement of longer time (more than a month), laborious section processing steps, requirement of sophisticated equipment's and costly ready to use kits limits extensive use of this technique. New method: The need for a modified staining technique is to overcome some of these hurdles. Here we describe a modification of Golgi-Cox staining involving reduced impregnation time (7 days), omitting tissue dehydration steps, and alterations in section processing steps. Different impregnation duration (7 days, 14 days, 1 month, 6 months and 10 months) effects on optimized staining of dorsal hippocampus and basolateral amygdala were investigated. Results: Modified Golgi-Cox staining method was found to be effective in staining rat hippocampus and amygdala. Impregnation for 7 days, 14 days and 1 month resulted in giving good results and they were comparable. However, artifacts were slightly elevated with 6 months group but not extensively. Impregnation for 10 months negatively affected the staining process. Comparison with existing method(s): Compared to existing methods the current method was found to be cost effective, fast, reliable and can be executed in labs where infrastructure is limited. Conclusions: Current modification considerably benefitted in obtaining better results (good clarity and lesser artifact) in a short time. Longer impregnated brain sections were found to be unsuitable for morphometric evaluation due to more stain precipitation and artifact. The modified technique can be used to study cellular architecture in other brain regions.