MEDICAL AND BIOLOGICAL STAINING TECHNIQUES 



10. Stain in the aldehyde-fuchsin solution from two to ten 

 minutes, taking care not to overstain, which can be avoided by 

 checking the slides (after rinsing in 95% alcohol) at intervals under 

 the microscope: the staining should be stopped as soon as the 

 beta cells stand out clearly in dark purple against a colourless or 

 faintly purple background. 



11. Rinse in two changes of 95% alcohol. 



12. Immerse for five to ten minutes in a third change of 95% 

 alcohol. 



13. Rinse in 70% alcohol. 



14. Rinse in distilled water. 



15. Stain in Ehrlich Haematoxylin for three to four minutes. 



16. Rinse in distilled water. 



17. Diff"erentiate by dipping three or four times in the acid 

 alcohol solution F. 



18. Blue in the lithium carbonate solution; or in running tap 

 water for five to ten minutes. 



19. Counterstain in the light green-orange-chromotrope solu- 

 tion H for 45 seconds. 



20. Rinse quickly with 0-2% acetic acid. 



21. Rinse in 95% alcohol. 



22. Immerse for two minutes in each of two changes of absolute 

 alcohol. 



23. Blot slides carefully. 



24. Immerse in xylol for two minutes. 



25. Immerse in another lot of xylol for five minutes. 



26. Mount in D.P.X. or Clearmount. 



Results : 



Granulation of beta cells, selectively stained dark purple with 

 the aldehyde-fuchsin. The cells of the pas intermedia and the 

 Herring bodies of the neutral lobe should have little or no affinity 

 for aldehyde-fuchsin. The delta cells are stained green, and the 

 acidophilic granules varying shades of orange. Nuclear chromatin, 

 purplish brown to reddish brown. Nucleoli are tinged bright 



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