WATER-INSOLUBLE CARBONYL COMPOUNDS 69 



3. Transfer to the Feulgen reagent for 15 min. and hold the 

 stained sections in the hydrochloric acid-sodium bisulfite solution. 



4. Examine sections immediately after washing in distilled water. 

 The stain will last for a few days if the sections are kept in sulfurous 

 acid solution. 



Method of Turchini et al. for Nucleic Acids 



SPECIAL REAGENTS 



Nucleic Acid Reagent. Dissolve 80 mg. of 9-phenyl (or methyl) - 

 2,6,7-trihydroxy-3-fluorone in 100 ml. 95% alcohol containing 15 

 drops cone, sulfuric acid. 



1 N Hydrochloric Acid. (Or 25% cone, hydrochloric acid in 90% 

 alcohol.) 



1 % Sodium Carbonate. 



PROCEDURE 



1. Fix the tissue (either plant or animal) in Bouin fluid. 



2. Prepare paraffin sections in the usual manner. 



3. If the methyltrihydroxyfluorone reagent is used: Hydrolyze 

 the deparaffinized sections in 1 A^" hydrochloric acid at 60° for 5 min. 

 wash with water, then alcohol, and treat for 5-10 min. with the re- 

 agent. Wash with several drops of 90% alcohol, then with 1% 

 sodium carbonate, rinse with water, and finally mount in balsam. 



3a. With the phenyltrihydroxyfluorone reagent: Use the same 

 procedure as in step 3 but carry out the hydrolysis in the cold in 

 alcoholic 25% hydrochloric acid for 3-5 min. 



WATER-INSOLUBLE CARBONYL COMPOUNDS 



While the fuchsin-sulfurous acid test can be used for the localiza- 

 tion of aldehydes in tissue, other histochemical tests employed by 

 Bennett (1939, 1940) will react with either aldehydes or ketones. 

 Bennett concluded that his tests for the carbonyl group were indica- 

 tive of ketosteroids in the outer layer of the fascicular region of the 

 adrenal cortex. These carbonyl reactions can only indicate lipid 

 aldehj'-de or ketone and are in no way specific for ketosteroids as 

 Gomori (1942) pointed out; however, if other supporting evidence is 

 at hand, it may be reasonable to ascribe a positive reaction to the 

 ketosteroids present in a particular tissue. Subsequent work of 

 Albert and Leblond ( 1946) indicated that '"plasmalogen" rather 

 than ketosteroids is revealed by the phenylhydrazine reaction. 



