STAINING, PRACTICAL AND THEORETICAL 



B. Distilled water . . . . . . 200 ml. 



Sulphuric or nitric acid, cone. . . 0-5 ml. 



Technique: 



1. Formalin fixed material is embedded in paraffin wax, and 

 sections, 4jLt in thickness are fixed to slides with glycerin albumen. 



2. Remove wax with xylol. 



3. Rinse with absolute alcohol. 



4. Pass through 95% alcohol. 



5. Pass through 80% alcohol. 



6. Immerse slides for five to ten seconds in the staining solution 

 at 80-90° C. 



7. Differentiate for one second in solution B. 



8. Dip and agitate slides in a beaker of cold distilled water for 

 one second. 



9. Differentiate further in 80% and 95% alcohol for one to two 

 seconds in each. 



10. Immerse in 80% alcohol for one second. 



11. Dip and agitate the slides in the still warm solution A for 

 one to two seconds. 



12. Return to 80% alcohol for one second. 



13. Repeat steps 11 and 12. 



14. Rinse in distilled water, 



15. Dehydrate by immersing for one second in each of 80%, 

 95% and absolute alcohol. 



16. Immerse in xylol for one minute. 



17. Immerse in a fresh lot of xylol for three minutes. 



18. Mount and examine. 



Results: 



Neurons stand out distinctly against a pale background, and 

 can be followed for a considerable distance. The cytons are stained 

 dark purple emphasizing the blue tint, while the dendrite and axon 

 processes and endings present a somewhat lighter shade, bluish to 

 reddish. Granules in the cell body as well as in the protoplasm 

 processes appear purple or reddish. Nuclei and nucleoli are well 

 differentiated. 



Reference: Spoerri, Rosette (1948). 



184 



