A new method for staining nerves and their endings using the Schiff reaction

The staining principle is based on the assumption that the nervous tissue contains some reducing agent of aldehyde nature and will give a positive reaction with the Schiff''s aldehyde reagent. This premise was later sustained by actual observations. The reaction constitutes a simple and reliable method for the staining of nerves and nerve endings of sensory, motor, cerebro-spinal and autonomic origin both whole mounts and in sections. Fresh or fixed (1% formic or acetic acid) tissues are stained in Schiff''s reagent, washed in SO2 and distilled water and counterstained with 0.5-1% aq. methyl green. Nerves are colored bluish purple, cytoplasm of nerve cells greenish pink, nuclei of motor sole plates and neurilemma cells green, elastic fibers faintly purple in pink tinted background. The prepn. of Schiff''s reagent is modified by using 6% H2SO3 to decolorize the basic fuchsin instead of HC1 plus K2S2O5 solution. The process is simpler and is completed within 2 hrs. The amt. of SO2 in the reagent can be controlled. The reagent is more sensitive.