Astrocytes 193 



comnfent: 



del Rio-Hortegas silver carbonate solution also tan be used in this 

 method. 



Astrocytes 



Ramon y Cajal's Gold Chloride Sublimate Method (mallorv, 1938) S 



fixation: Fix thin slices of tissue in: 



formalin 15.0 ml. 



ammonium bromide 2.0 gm. 



distilled water 85.0 ml. 



37°C: 1 day 



sectioning: frozen sections, 15 microns thick. 



solutions: 



Gold chloride sublimate solution: 



mercuric chloride crystals {not powder) 0.5 gm. 



gold chloride, 1 ^]q aqueous 6.0 ml. 



distilled water 35.0 ml. 



Prepare fresh, using acid-clean glassware. Pulverize mercuric chlo- 

 ride; add to distilled water. Heat gently. When dissolved, add gold 

 chloride, and filter. 



del Ri'o-Hortega's carbol-xylol-creosote mixture: 



creosote 10.0 ml. 



phenol (carbolic acid), melted 10.0 ml. 



xylene 80.0 ml. 



procedure: 



1. Place sections in 1% formalin. 



2. W'ash quickly in distilled water, 2 changes. 



3. Place in freshly prepared gold chloride (in acid-clean glassware). 

 Flatten sections, keep in dark at room temperature: 4-6 hours. 

 When sections appear purplish, examine for astrocytes. 



4. W^ash in distilled water: 5-10 minutes. 



5. Fix in 5% sodium thiosulfate (5 gm./lOO ml. water): 5-10 min- 

 utes. 



6. Wash in distilled water, several changes. 



7. Float on slide, dehydrate with 95% alcohol. 



