Nerve Fibers and Ending 205 



?>. Rinse in distilled water, 2 changes. 



4. Reduce: 5-10 minutes, agitating for first minute: 



Elon 0.2 gm. 



sodium sulfate, anhydrous 1 0.0 gm. 



hydroquinone 0.5 gm. 



sodium borate 0.1 gm. 



distilled water 100.0 ml. 



5. Wash in distilled water, 4-5 changes. 



6. Treat with silver nitrate, 1% aqueous (1 gm./lOO ml. water): 

 10-20 minutes, room temperature or .S7°C. 



7. Wash in distilled water, 2-?> changes. 



8. Reduce (step 4 above). 



9. Wash in distilled water, 4 changes. Examine. If nerve fibers shoAv 

 distinct differentiation, dehydrate, clear, and mount. If not well 

 differentiated, repeat steps 6, 7, 8, and 9 until desired results are 

 reached. 



10. Toning may be done in 0.2% gold chloride (0.2 gm./lOO ml. 

 water) until greyish in color. Fix, dehydrate, clear, and mount. 



'"^ ' Chloral Hydrate-Silver Method (nonidez, 1939) B 

 fixation: 24 hours or longer (up to 3 days): 



chloral hydrate 25.0 gm. 



50% ethyl alcohol 100.0 ml. 



procedure: 



1. Wipe off excess fixative and put blocks in: 



95% ethyl alcohol 60.0 ml. 



ammonia, concentrated 4 drops 



Leave for 24 hours, but change at least once, particularly if blocks 

 are large or contain a large ainoimt of fat. 



2. Rinse in distilled water: 5 minutes. 



3. Place in 2% aqueous silver nitrate (2 gm./lOO ml. water) in dark, 

 37-40°C: 5-6 days. Replace silver solution after 2 days, or as soon 

 as it becomes brownish in color. 



4. Rinse in distilled water: 2-3 ixiinutes. 



5. Reduce for 24 hours in: 



pyrogallol 2.5-3.0 gm. 



formalin 8.0 ml. 



distilled water 100.0 ml. 



