MUCOID DEaEXEh'ATWy ^27 



MUCOID DEGENERATION 



ATnoin in its typical form, is a compound protein, consisting of a 

 :\Iucm, in Its IH ica ' ^ ^^^^i^ carbohydrate, rjlucosamm. 



S:;:r:t;r1>oerwir:crds mucin ;Ma. . substanee reducing 

 Sno-'s so ution. Mucin is acid in reaction, probably because of 



: thZc'dvL* It r;rdily dissolved in very weak alkaline solu^ 

 n s is prec Stated br acetic acid, and its physical properties when 

 n inrirarfc ui.e characteristic. The t;""™-". >;---; ^tl 

 Wv covers a number of related but distinct bodies. Some, sucli as tne 

 "fc. r^c^rare readily distinguished by not b^ing preeipi a - b^ 

 acetic acid and bv being alkaline in reaction: others jield ieducin„ 

 suWances without previous decomposition with acids (paramucm ; 

 while even Tmong tile "true" mucins certain differences in solubility 



'tnThe mammalian body we find mucin <"=.<;"■■>;!"= '■;,f™2f'ta tt 

 calitics: (1) as a product of secretion of ePf ^^^ Is (2^ m the 

 interstices of connective tissue, especially of t ndo. . (^^^ J^^J 

 Hanee of svnovial fluid to mucin is more physica than ™emical.) 

 Thpre is a so evidence that mucin or a related body constitutes the 

 cement suSance between all the bodycells. Corresponding to these 

 Zc^iief sources of mucin we And mucoid degeneration occnrring as 

 ;^stincrprocesses in mucous membranes (or tissues derived therefrom) 



'^Eprthl'ilLT M^cin!-! epithelial mucin represents a distinct prod- 

 uct ospcialized cells, it is questionable if the ordinary app. cation 

 o th tenndegeneration in the sense of the conversion of eell-proto- 

 nlasr^ nto mucin, is correct. Certainly the mucin formation of ca_ 

 t'arhal nflaliation is merely an excess of a -"-> -- '^j^^;^ 

 tbP deo-enerative changes that may be present m the epithelial cells are 

 nroducedbv the cause of the inflammation, and are not dependent upon 

 mucirfornn. ion. Even in the extreme example of mucoid degenera- 

 tion" en i^ carcinomas derived from mucous membranes (the so-c<dU^ 

 ••?ollok""ancers"), the epithelial degeneration is not necessanh to 

 he nterme"ed as a conversion of cell-eytopla,sm into mucin, but is 

 largely due to the pressure of secreted mucin upon the cells within 

 ,.For special consideration «e Cutter and Oies, .^mer. .Tour, rli.vsiol.. IWl 



""■ '^?- , ,„ ■. „ P.ll, ion (14) 23) savs that the long controversy 



so. Sohadc IZeit. exp. Patli.. l-HJ ' ','• -;J' ,|-' ,,„„„crtive tissue is settled 



eoneernins the intercellular '"''»;»„"" „°/""^™„k?"rt"S p. 321). who found 



trpr„™irr;l5':ttS:rand"f:,dr|ucin is indicate., ,. ^ 

 logical inter-reactions (Elliott, Jour. Infect. Dis., 1014 (la), oUi). 



