Alkaline lead citrate: a selective stain for glutaraldehyde precipitates of indolamines and primary catecholamines in electron microscopy.

Test-tube experiments proved that alkaline lead citrate (Reynolds, 1963), which is generally used as an electron-opaque stain, specifically reacts with precipitates formed by glutaraldehyde and biogenic amines (indolamines, primary catecholamines). Glutaraldehyde/osmium tetroxide fixation and staining of thin sections with alkaline lead citrate is recommended as an optimal preparation method of studying the above-mentioned amines at a fine structural level.