title: Zinc-aldehyde fixation for light-microscopic immunocytochemistry of nervous tissues.
abstract: Two procedures are described for vascular perfusion of the nervous system with a zinc-aldehyde fixative. The procedures, simple and economical, combine the advantages of perfusion fixation with an aldehyde solution and matrix stabilization by a mordating agent, and improve the sensitivity of the peroxidase-antiperoxidase (PAP) method for the immunocytochemical localization of several antigens. Procedure A is intended for the light-microscopic immunostaining of cellular elements containing high concentrations of antigen. Penetration of the immunoreagents is adequate without the use of detergents. Procedure B is particularly advantageous for the light-microscopic immunostaining of cellular elements that contain low concentrations of antigen, and for high-resolution microphotography. With procedure B, the tissue penetration of immunoreagents is more limited than with procedure A; however, neuronal cell bodies and dendrites are more easily penetrated by the immunoreagents than are axons. Neuronal cell bodies and dendrites thus become clearly detectable in the light-microscope, even when they are surrounded by numerous immunoreactive axon terminals, and especially after the blockage of axoplasmic transport by the topical injection of colchicine.
mesh_terms: D000818:Animals; D000941:Antigens / Q000032:analysis; D002415:Cats; D005404:Fixatives / Q000008:administration & dosage; D005557:Formaldehyde; D005968:Glutamate Decarboxylase / Q000032:analysis; D006651:Histocytochemistry / Q000379:methods*; D007124:Immunoenzyme Techniques; D008253:Macaca mulatta; D009420:Nervous System / Q000276:immunology; D009474:Neurons / Q000032:analysis*; D010477:Perfusion / Q000379:methods*; D011108:Polymers; D011817:Rabbits; D051381:Rats; D012459:Salicylates; D015032:Zinc
chemical_list: D000941:Antigens; D005404:Fixatives; D011108:Polymers; D012459:Salicylates; D005557:Formaldehyde; D005968:Glutamate Decarboxylase; D015032:Zinc; C003043:paraform