SECTION TWO 



ORCINOL - NEW FUCHSIN 



A selective stain for elastic tissue 



Solutions required: 

 A. New fuchsin . . . . . . 2 gm. 



Orcinol . . . . . . . . 4 gm. 



Distilled water . . . . . . 200 ml. 



Boil for five minutes ; then add : 

 Ferric chloride (FeCla), 15% . . 25 ml. 

 and boil for a further period of five minutes. 



Allow the solution to stand until cold; then collect 

 the precipitate by filtration: washing and drying is 

 stated to be unnecessary. 



Dissolve the precipitated orcinol-new fuchsin in 

 100 ml. of 95% alcohol and use this as the elastin stain. 



Technique: 



1. Material may be fixed in 10% formalin or saturated aqueous 

 mercuric chloride or Zenker, etc. 



2. Fix sections to slides, dewax and pass through absolute 

 alcohol as usual. 



3. If a mercury-containing fixative has been used, treat sections 

 for the removal of mercurial precipitate by the standard method, 

 afterwards rinsing with 90% alcohol. 



4. Stain in the orcinol-new fuchsin for fifteen minutes at 37° C. 



5. Differentiate for five minutes in each of three changes of 

 70% alcohol. 



6. Dehydrate in absolute alcohol; clear in xylol, and mount in 

 D.P.X., or Cristalite, or Clearmount, etc. 



Results: 



Elastic fibres: deep violet. Collagen: unstained. 



Notes: 



{a) The authors reported that they used the stain on human 

 skin and aorta, and the following tissues of the mouse: liver, 

 kidney, spleen, stomach, duodenum, colon, pancreas, heart, 

 testes, seminal vesicles, ovary, uterus, aorta, pituitary, salivary 

 gland, bone, striated muscle, and thyroid; and in all cases only 

 elastic tissue was stained. 



335 



