CHAPTER XXXVIII 



CONNECTIVE AND ELASTIC TISSUES 



CONNECTIVE TISSUE 



956. General Stains for Connective Tissue. Connective tissue, 

 elastic tissue, and smooth muscle are all normally acidophilous. 

 Collagen, the distinctive element of connective tissue, absolutely 

 requires " acid " dyes for the production of a permanent stain, 

 whilst elastic tissue and muscle will also fix " basic " dyes. Collagen 

 has a special affinity for Saurefuchsin and Wasserblau. Elastin 

 has a strong affinity for acid orcein, whilst muscle has no special 

 affinity for either, but stains energetically with picric acid. 



Picro-sdurefuchsin is much used and very convenient as a 

 general differentiating stain, but not to be recommended for 

 cytological detail. See Schaffer, Zeit. wiss. ZooL, Ixxx, 1905, 

 p. 176. 



E. and T. Savini recommend Benda's Picro-Saurefuchsin, 

 §326. 



Ehrlich-Biondi mixture gives connective tissue red, but 

 smooth muscle redder still. 



Unna's Wasserblau-orce'in for distinguishing connective tissue 

 and muscle has been given, § 930. It works after all fixatives. 

 Stain long, and dehydrate preferably with acid alcohol. 



Freeborn {Amer. Mon. Mic. Journ., 1888, p. 231) recom- 

 mends (for sections) picro-nigrosin, made by mixing 5 c.c. of 

 1 per cent, aqueous solution of nigrosin, with 45 c.c. of aqueous 

 solution of picric acid. Stain for three to five minutes, wash 

 with water, and mount in balsam. Connective tissue blue, 

 nuclei blackish, the rest yellowish. 



Ramon y Cajal's picro-indigo-carmine gives connective-tissue 

 fibres dark blue, with red nuclei. 



S. Mayer {Sitzb. k. Akad. Wiss., Ixxxv, 1882, p. 69) recom- 

 mends for staining fresh tissue Violet, B, § 357. Elastic fibres 

 and smooth muscle also stain, but of different tints. 



DuBREUiL (C. R. Ass. Anat., vi Sess., 1904, p. 62) uses a mixture 

 of 23 volumes 1 per cent, picric acid and 2 volumes 1 per cent, 

 methyl blue — with a previous stain with carmalum or safranin. 



For Ranvier's method of artificial oedemata for the study of 

 areolar tissue, see his Traite, p. 329. 



957. Unna's Orcein Method. {Encycl. mik. Technik., 1910, 

 p. 250). Sections are stained for ten minutes in Griibler's poly- 



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