RETICULAR AND COLLAGEN IC 306 



FIBERS 



REVIVAL OF VINEGAR EELS 



tissue studied. There are, however, 

 several which are stains (Kinney's 

 Method and Biebrich Scarlet and 

 Picro-Anilin Blue). 



Reticular and Collagenic Fibers in frozen 

 sections (Krajian, A. A., Arch. Path., 

 1933, 16, 376-378). Cut frozen sections 

 5-lOii thick of tissue fixed in 10% forma- 

 lin and wash in 3 changes aq. dest. 

 After treating with 10% aq. ammonium 

 hydroxide at 60°C. for 15 min. (in par- 

 affin oven) wash them again in 3 changes 

 aq. dest. Place in 0.3% aq. potassium 

 permanganate for 5 min., wash in aq. 

 dest. for a few seconds and decolorize 

 in 1.5% aq. oxalic acid till brown color 

 has j ust disappeared . Wash thoroughly 

 in aq. dest. and place in 5% aq. silver 

 nitrate at 60°C. for 1 hr. Wash in 2 

 changes aq. dest. and place in ammonia- 

 cal silver nitrate solution at 60°C. for 

 15 min. (To make this solution add 

 6 drops 10% aq. sodium hydroxide to 

 8 cc. 10% aq. silver nitrate which gives 

 a brownish black precipitate. Add 

 fresh 10% aq. ammonium hydroxide 

 drop by drop until only a few small 

 particles of the precipitate remain. 

 Dilute to 28 cc. with aq. dest.). Wash 

 sections quickly in 3 changes aq. dest. 

 Treat them with 30% formalin at 60°C. 

 1-3 min., wash in large amount of tap 

 water and mount on slides. Cover 

 sections with a little absolute alcohol 

 and blot into position. Then complete 

 dehydration with absolute, blot, clear 

 in equal parts aniline oil and xylol. 

 Wash in xylol and mount in gum dammar 

 or Canada balsam. Reticulum black; 

 collagen, brown. 



Reticulocytes. These are the stages recog- 

 nized in the red series before the as- 

 sumption of properties of Erythrocytes. 

 An excellent review of the properties of 

 reticulocytes is supplied by Orten, J. 

 M., Yale J. Biol. & Med., 1933-34,6, 

 519-539. Reticulocytes can easily be 

 identified by supravital staining with 

 brilliant cresyl blue. First make a thin 

 film of the dye on slide by allowing a 1% 

 solution in absolute alcohol, spread 

 evenly, to evaporate. Then mount fresh 

 blood, ring withvaseline and observe. To 

 make relatively permanent specimens, 

 remove the cover glass after 2 min . , smear 

 dry and color by Wright's Stain. The 

 supravital staining with cresyl blue is 

 inhibited by certain substances (Heath, 

 C. W. and Daland, G. A., Arch. Int. 

 Med. , 1931 , 48, 133-145) . For a calcula- 

 tion of experimental error in reticulo- 

 cyte counts, see Marcussen, P. V., 

 Folia Haemat., 1938-39, 61, 49-64 and 

 for fragility tests, see Mermod, C. 

 and Dock, W., Arch. Int. Med., 1935, 

 55, 52-60. Resistance to hypotonic 



sodium chloride solutions is described 

 by Daland, G. A., and Zetzel, L., Am. 

 J. Med. Sci., 1936, 191, 467-474. The 

 protoporphyrin content of reticulocytes 

 can be estimated by the fluorescence 

 technique. Watson and Clarke (C. J. 

 and W. O., Proc. Soc. Exp. Biol. & 

 Med., 1937, 36, 65-70) have discovered 

 that it is greater than in erythrocytes 

 and that brilliant cresyl blue is pre- 

 cipitated by protoporphyrin which may 

 explain the characteristic staining of 

 reticulocytes by this dye. 



Reticulo-Endothelial Blockade. Supposed 

 to be a method whereby R. E. cells are 

 so blocked by the ingestion of one 

 foreign material that they are unable to 

 take in another. For experiments with 

 India ink and brilliant vital red and 

 critical statement, see Victor, J., Van 

 Buren, J. R., and Smith, H. P., J. 

 Exper. Med., 1930, 51, 531-548. 



Reticulo-Endothelial System. This is by 

 definition made up of the reticular cells 

 of the connective tissues plus certain 

 special endothelial cells chiefly located 

 in the spleen, liver, bone marrow, 

 adrenals and lymph nodes. All have 

 the common property of phagocytosing 

 particulate matter such as trypan blue, 

 carbon, etc. These, and possibly 

 others, may leave their moorings and 

 become free cells when they become 

 known as Monocytes or Macrophages. 

 A better term is the "system of macro- 

 phages" (or big eaters) in which empha- 

 sis is placed on function not origin. See 

 Vital Staining. 



Retina, see Eyes. 



Retterer's Stain for muscle. Fix in 10 

 parts 80% alcohol plus 1 part formic 

 acid. Stain paraffin sections with alum 

 carmine. Muscle light red, all connec- 

 tive tissue unstained. 



Revival of Vinegar Eels after Ultrarapid 

 Cooling. — Written by B. J. Luyet, 

 Dept. of Biology, St. Louis University. 

 January 15, 1951 — A drop of a con- 

 centrated vinegar eel suspension, ob- 

 tained by centrifugation, is deposited 

 on a glass slide and most of the remain- 

 ing vinegar is blotted off. Then a drop 

 of 30% ethylene glycol is added to the 

 squirming mass in order to reduce some- 

 what the water content of the worms. 

 After about 5 minutes the excess ethyl- 

 ene glycol is blotted off, and the eels, 

 still moving actively, are "wiped up," 

 in a thin layer, on very thin pieces of 

 mica (about 5 mm. on a side and about 

 35 micra thick). The eels, supported 

 on this mica slip, are then immersed in 

 liquid air. After about one minute 

 they are removed, and, by means of a 

 vigorous shake of the hand, the droplet 

 of liquid air which may adhere to the 



