A Silver Impregnation Method for Nervous Tissue Suitable for Routine use with Mounted Sections

Abstract
A simple, reliable silver impregnation method for nervous tissue is described for tissues fixed in various fixatives including formalin, Bouin, and Sum. Sections are impregnated in a solution containing 1 g Protargol, 2 ml of a 1% Cu(NO3)2 solution, 2 ml of a 1% AgNO3 solution, and 2-4 drops 30% H2O2 in 100 ml distilled water. Sections are impregnated 4-5 days at 37 C and thereafter reduced in a hydroquinone-formalin solution. This is followed by gold toning and subsequent reduction, dehydration and mounting. This method has been found to be very reliable and selective.