An electron stain for elastic fibers using orcein.

Abstract

Orcein was found to be useful as an electron-opaque stain for elastic fibers in epoxy-sections. Ultra-thin sections of aorta were treated with elastica stain containing 0.1-0.3% orcein and counterstained in uranyl acetate and lead citrate. Elastic fibers were densely and specifically demonstrated in the stroma and near smooth muscle cells. The result of orcein staining has a comparable appearance under both light and electron microscopes.