STAINING, PRACTICAL AND THEORETICAL 



faintly stained. Erythrocytes : reddish brown. Collagenous fibres : 

 pale rose to brownish pink. Elastic fibres: dark brown to black. 

 Senile degenerated connective tissue (collacin, elacin and collastin) : 

 various shades of dark grey and blue. Cartilage: metachromatic 

 (varying shades of) purple. Decalcified bone : light brown. Keratin : 

 blue (poorly stained). Stratum lucidum, dark red; keratin layer 

 may be light blue or light pink or colourless depending upon the 

 tissue and the degree of decolorization. Inner root sheath of the 

 hair: deep blue. Melanin granules: green to black. Other pig- 

 ments: unstained. Bacteria and myceha: deep blue. Demodex 

 folliculorum in hair follicles: brown with blue granulations. 



Reference: Pinkus, H. (1944). 



ORCEIN -PICRO FUCHSIN 

 For elastic and collagen fibres 



Solutions required: 



A. Orcein (Unna) 1% in 80% alcohol 100 ml. 

 Hydrochloric acid, cone. . . i ml. 



B. Picro-fuchsin (Van Gieson). 



Technique: 



1. Sections are mounted on slides and brought down to 70% 

 alcohol in the usual manner. If tissues have been fixed in a fluid 

 containing mercury, the mercurial precipitate is removed by the 

 standard technique. 



2. Immerse in orcein solution (recipe as above) for half an 

 hour or longer if necessary; then rinse in acid alcohol. 



3. Rinse in 70% alcohol; then in water. 



4. Stain with picro fuchsin (Van Gieson) for three to five min- 

 utes. 



5. Rinse rapidly (not more than a few seconds) in water. 



6. Dehydrate rapidly; clear, then mount. 



Results: 



Collagen fibres are stained red ; elastic fibres, brown ; erythro- 

 cytes, epitheUa, muscle, etc., yellow. 



Reference: Carleton, H. M. & Leach, E. H. (1947) p. 126. 



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