A RELIABLE METHOD FOR GOLGI STAINING OF RETINA AND BRAIN-SLICES

Although the classical Golgi method is a powerful means for structural analysis of the brain, it is generally considered to be an unpredicta ble technique making anatomists wary of using it. Often, even when suc cessful staining has occurred, deposits of silver chromate crystals on the surface of the tissue obscure examination. This paper describes a simple procedure for Golgi impregnation of retina and brain slices so that good, even staining is obtained and crystal formation is avoided . The most outstanding feature of the method is the consistency of res ults. This consistency is due to two factors: (1) the accurate determi nation of the optimal chromation by measuring the rise of pH in the so lutions and (2) the uniform penetration of dichromate and silver nitra te to the specimen by using a freely hanging, sandwiching technique. W e suggest that the method described here can be applied to other parts of the nervous system and will be a reliable way to identify and bett er classify new cell types.