Orcien Staining Of Elastic
Orcien is a complex mixture of related compounds originally derived from lichens but now made synthetically. The synthetic product is often considered to be superior in staining abilities to the natural product and is invariably the material provided from laboratory supply companies. It was one of the first dyes used to selectively stain elastic fibres, and demonstrates both thick and thin fibres in a single section. The simplest technique is likely that of Taenzer-Unna, which uses a 1% orcien solution in 1% acid alcohol for an appropriate time, recommendations varying from a half hour to overnight. This same method is also used to stain the rough endoplasmic reticulum in ground glass cells in liver biopsies. Once stained, orcien is fairly resistant to extraction and other techniques can be applied to differentiate tissue constituents.
Orcien staining of elastic fibres has frequently been incorporated into other staining techniques, notably the trichrome methods, the combinations usually being referred to as pentachrome stains. These methods may stain elastic fibres as a seperate step, or may incorporate orcien into a staining solution to accomplish the same thing. Such methods are often based on Unna's technique which used the orcien in a solution with aniline blue or one of its constituent dyes, but add other dyes to the staining mix to differentiate between collagen and other structures more effectively.
|Orcien Staining Methods|
Last updated January 2019