Staining for Nerve Fiber and Cholinesterase Activity in Fresh Frozen Sections

Abstract

Methods of staining axons and myelin sheaths, and combination staining of axons or myelin and cholinesterase, in sections from unfixed frozen tissue have been described and have been applied to skeletal muscle, smooth muscle, blood vessels, skin, iris, lacrimal glands, optic nerves and autonomic ganglia. A modification of the silver method was utilized for staining axons, a modification of Baker''s acid hematein technic for staining myelin, and a modification of the acetylthiocholine method for localizing cholinesterase activity. The present methods, which are reproducible and relatively simple, permit sections of the same specimen to be used for other staining technics, including those that require fresh frozen sections. Combination staining of cholinesterase and nerve terminals is believed to have wide application in studies of the structure of synapases, especially the neuromuscular junction.