Neurological Staining 191 



Note: In neurological technics the methods sometimes employ section- 

 staining and sometimes employ block-staining. The letters S and B will 

 be used in the headings of this c hapter to indicate which type of staining 

 is being described. 



Neurological Staining 



Heidelberger's Victoria Blue (.modified by proescher, 1934) S 

 fixation: 10% formalin. 



procedure: 



1. Cut frozen sections, 10-15 microns. 



2. Place sections in distilled water. If not stained at once they may 

 be stored in 10% formalin for 24 hours, but no longer. 



3. Stain in Victoria blue B, C.I. 44045, saturated aqueous solution: 

 12-24 hours. 



4. Wash rapidly in distilled water and mount on albumen-coated 

 slides. Blot with filter paper and dry in air. 



5. Expose to ultraviolet light: 30 minutes. 



6. Immerse in N/20 iodine solution (aqueous): few seconds. 



7. Remove from iodine, blot, air dry for 10 minutes. 



8. Differentiate in xylene-aniline (1:1), clear in 2 or 3 changes of 

 xylene, and mount. 



results: 



glia cell bodies and fibrils — light to deep blue 



nerve cell bodies, dendrites, and axis cylinders — faintly stained 



comments: 



1. Staining time can be shortened to 30-35 minutes at 56°C. 



2. Proescher experimented ^vith oxidizing agents — potassium chro- 

 mate and dichromate and hydrogen peroxide — and found they 

 could be substituted for ultraviolet. Potassium dichromate was 

 most successful and can be used as a 0.5% aqueotis soltition for 30 

 minutes. 



3. Victoria bkie may be replaced by methyl violet 2B, ethyl violet, or 

 crystal violet. 



