280 ASCORBIC ACID 



cysteine may also contribute appreciably to the decomposition of hydro- 

 gen peroxide. 



(b) Chondroitin-Sulfuric Acid Complex. There is lack of accord among 

 investigators as to variations in chondroitin-sulfiiric acid in the mesenchy- 

 mal supporting tissues of normal as compared to scorbutic animals. Hojer^ 

 found a collagen atrophy in scurvy especially marked in cartilage^^ in and 

 near the columns of the proliferating zone, in and near the epiphyses. Sec- 

 tions stained with methylene blue did not appear to be different from normal 

 in their presumable content of chondroitin-sulfuric acid. Meyer, ^* on the 

 contrary, reported that cartilage sections of scorbutic guinea pigs were de- 

 ficient in chondroitin-sulfuric acid. His observations were based on staining 

 reactions. Sadhu^^ found that the chondroitin-sulfate content of skin and 

 bones was considerably decreased in scorbutic animals. Bradfield and 

 Kodicek^^ did not find marked difference in the toluidine blue-staining re- 

 actions of sections through skin wounds of scorbutic as compared to normal 

 guinea pigs and interpreted the results as indicating that sulfated polysac- 

 charides cannot account for the abnormal abundance of polysaccharide 

 material Avhich they found in the scorbutic wounds. Meyer and associates-^ 

 have shown that the protein or proteins to which some of the sulfate esters 

 of connective tissue are bound are distinct from collagen, since they contain 

 tyrosine and tryptophan. Because of the importance of ascorbic acid for the 

 metabolism of tryosine^** it seems possible that the vitamin may perform 

 a special function in those chondroitin-sulfuric acid complexes containing 

 this amino acid. 



Bradfield and Kodicek^^ evaluate the role of ascorbic acid with respect 

 to the interfibrillar substance as follows: "Evidently vitamin C has a pro- 

 found influence on mucopolysaccharide metabolism, but whether direct or 

 indirect, and whether affecting the kinds of mucopolysaccharides produced, 

 or the mucolytic enzymes for their disposal, is at present uncertain." 



It is obvious from this discussion that many of the problems pertaining 

 to connective tissue remain unsolved. The lack of specificity in the reactions 

 of both the enzymes^^ and stains"- ^-"^^ used in the histochemical studies 



*^ The data for cartilage are presented since there are none for connective tissue. 

 *8 A. W. Meyer and L. M. McCormick, Studies in Scurvy, Stanford Univ. Publ., 



Univ. Ser. Med. Sci. 2 (1928). 

 89 D. P. Sadhu, Indian J. Physiol, and Allied Sci. 6, 49 (1952). 

 9" R. R. Sealock, B. Ziegler, and R. L. Driver, J. Biol. Chem. 128, l.xxxix (1939). 



91 J. H. Humphrey, Biochem. J. 40, 442 (1946). 



92 L. Lison, Histochemie animale, mdthodes et problems. Gautier-Villars, Paris 

 (1936). 



93 B. Sylvan, Acta Chir. Scand. 86, Swpvl. 66 (1941). 

 9^ K. Meyer, Physiol. Revs. 27, 335 (1947). 



96 G. Wislocki, H. Bunting, and E. W. Dempsey, Am. J. Anat. 81, 1 (1947). 

 96 R. D. Lillie, Anat. Record 108, 239 (1950). 



