STAINING, PRACTICAL AND THEORETICAL 



Technique: 



1. Fix material in io% formalin, or 80% alcohol, or 1% 

 trichloracetic acid in 80% alcohol, or Carnoy's fluid, or Bouin, 

 and embed in paraffin wax in the usual way. 



2. Fix sections to slides; dewax with xylol; then take down to 

 distilled water through the usual graded alcohols. 



3. Stain in Harris haematoxylin for six minutes. 



4. Rinse thoroughly in running water, for two to three minutes. 



5. Rinse in distilled water. 



6. Wash successively with 50%, 70%, 80%, and 95% alcohols. 



7. Stain for five minutes in orange G. 



8. Rinse well in two changes of 95% alcohol. 



9. Stain with solution H (Papanicolaou stain EA36) for two 

 and a half minutes, with occasional agitation. 



10. Rinse thoroughly in each of three jars of 95% alcohol. 

 (Do not use the jars that were used at step 8, above.) 



1 1 . Dehydrate thoroughly with two or three changes of absolute 

 alcohol. 



12. Clear in xylol and mount in Cristalite, Clearmount, D.P.X. 



or Emexel. 



Results : 



Keratin: bright orange, while compact collagen appears orange- 

 red. 



The authors state that the method has been pre-eminently 

 successful in the identification of keratin per se. As a typical 

 example, a section of well cornified oral mucous membrane with 

 long epithelial pegs showed basal cells that stained green. Succes- 

 sive layers of the stratum germinativum displayed a variety of 

 colours ranging from deep red to bright orange of the superficial 

 keratin. The corium presented a loosely textured lamina propria 

 characteristically stained green. The deeper segments of the more 

 compactly collagenous submucosa stained orange-red. 



Notes: 



(a) The authors state that the Papanicolaou technique was 

 applied by them to various keratinizing epithelia, including: 

 hairless skin, hairy skin, feathers, nails, claws, hooves, and well- 

 cornified oral mucosa. 



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