Perfusion‐fixation of the brain with chrome‐osmium solutions for the rapid Golgi method

Abstract

Abstract The characteristics of rapid Golgi impregnations of neurons in the brains of opossums, rats, rabbits, chinchillas, and cats, obtained with a method employing intracardiac perfusion with osmium tetroxide‐dichromate fixatives, are reported. Observations on all subdivisions of the brain were compared with immersion‐fixed Golgi preparations and formalin‐perfused brains prepared by Nissl or reduced silver methods. Perfusion‐fixation yielded more uniform and extensive Golgi impregnations, which were more representative of the varieties of neural structures than in immersion‐fixed preparations. The morphological details of fine neuronal processes, delicate dendritic branchlets and spines, and fine elements of the axonal plexuses were more clearly and consistently demonstrable. Observations with the polarizing microscope suggested that the Golgi impregnations contained silver dichromate and/or silver monochromate. The procedures and the predictability, nature, and histological reliability of the rapid Golgi method are discussed.