50 ' MICROSCOPIC TECHNIQUES 



PROCEDURE 



1. Follow steps 1 and 2 for Bauer-Feulgen stain. 



2. After bringing down to distilled water, stain nuclei with 

 hematoxylin. 



3. Transfer to fresh carmine stain and after 20 min. wash in 

 three changes of methanol, dehydrate in acetone, clear in toluol, 

 and mount in balsam. 



4. Run negative control sections as in step 7 for the Bauer- 

 Feulgen method but apply the carmine stain above. 



Result. The glycogen will appear brilliantly red. 



Gomori Procedure for Glycogen and Mucin 



SPECIAL REAGENTS 



Fixative. One of the alcohol fixatives such as alcohol-picric acid- 

 formalin (page 48) for glycogen. Any routine fixative for mucin. 



0.5% Collodion in Alcohol-Ether Solution. 



5% Chromic Acid. 



1-2% Sodium Bisulfite. 



Silver-Methenamine Stock Solution. Add 5 ml. 5% silver nitrate 

 soln. to 100 ml. 3% methenamine ( hexamethylenetetramine ) soln. 

 Shake until the initial heavy white precipitate disappears, and 

 store in refrigerator. 



Alkalized Silver-Methenamine Solution. To 25 ml. silver-methena- 

 mine stock soln. add 25 ml. distilled water and 1-2 ml. 5% borax 

 (Na2B4O7.10H2O). 



0.1 % Gold Chloride. 



2—3% Sodium Hyposulflte. 



PROCEDURE 



1. Fix tissue and prepare paraffin sections as usual. 



2. Run sections through xylol, alcohols, and water. (For glyco- 

 gen, protect sections on slides by dipping into collodion soln. before 

 transferring to the final alcohol soln.) 



3. Place slides in 5% chromic acid for 1 — 1.5 hr. 



4. Wash in running tap water for 10 min. and treat with the 

 bisulfite soln. for 1 min. to remove remaining traces of chromic acid. 



5. Wash in running tap water for 5 min., rinse in distilled water, 

 and incubate at 37-45° in the alkalized silver-methenamine soln. 

 Examine sections under microscope every 15 min. Staining is com- 



