The use of cryostat microtomy in a simplified Golgi method for staining vertebrate neurons

The use of cryostat and cryoprotective measures for processing Golgi impregnated brain tissue has shortened and simplified the method without loss of quality. The procedure contains the following steps: (1) the animal is perfused with phosphate-buffered paraformaldehyde and the brain removed for storage in the fixative; (2) the brain is rinsed in buffer, cut into 3- to 6-mm-thick blocks and placed in Ramon-Moliner's impregnation solution for 2-4 weeks; (3) the brain tissue is cryoprotected by soaking in 30% sugar for 24 h and then frozen and cut on a cryostat, the sections, being collected directly on slides; and (4) the mounted sections are then alkalized, fixed, rinsed, counterstained and rinsed again before dehydration, clearing and coverslipping.