A combination of Golgi impregnation and fluorescent retrograde labeling

Central nervous system structures containing neurons labeled by the fluorescent tracers Fast blue (FB), Diamidino yellow dihydrochloride (DY), Rhodamine B isothiocyanate (RITC) and Rhodamine-labeled latex microspheres (RLM) were processed with the Golgi method. The goal was to improve the visualization of the fluorescent labeled neurons and to allow their ultrastructural examination. While the fluorescence of FB and RITC is greatly attenuated by the Golgi method, RLM and DY are still visible in Golgi-impregnated neurons. However, it is usually necessary to remove the silver precipitate by gold-toning.