214 \■ETF.RI^'Al<^' pAxiior.ocw 



urc tij react to iodine it is difficult to differentiate from amyloid 

 change. 



Tissues Affected. — Afnscular tissue, involuntary muscle, 

 especially of the blood vessels, voluntary nuiscle and heart mus- 

 cle are subject to hyaline changes. Connective tissue is less fre- 

 quenth- in\'olved and epithelium rarely, if ever. 



Effects. — When hyaline has been formed in small quanti- 

 ties and the cause is removed the hyaline substance is resorbed 

 and the aft'ected cells repaired. If the production of liyalin has 

 replaced the protoplasm of large cell masses, especially of mus- 

 cular cells, the area will prc.ibablv not l)e repaired with muscular 

 tissue, though it mav be with fibrous tissue, provided the cause 

 is removed. 



MUCOID CHANGES. 

 Physiologic. 



DEFINITION. 



ETIOLOGY— Phvsioloqic, patliologic. 



APPEARANCE. 



MacyoscoI>ic. 



Microscopic. 

 TISSUE AEEECTED— Connective^ epithelium. 

 EFFECTS. 



The transformation of cell protoplasm into mucus is evident 

 in the physiologic production of mucus in the surface epithelium 

 of mucous membranes as well as in mucous glands. The physi- 

 ologic con^•ersion of protoplasm into mucus is the result of in- 

 tracellular enzyms. or at least depends upon protoplasmic activ- 

 ity. As the mucus is produced the cell becomes enlarged and 

 ultiniateK- ruptures, discharging the mucus. The mucus mav be 

 formed onU- in the distal end of the cell cjr it may entirely re- 

 place the prr)toplasm of the cell. In the former the remaining 

 protoplasm <.if the cell regenerates the portion destroved. In the 

 latter the adjacent cell multiplies, thus filling the gap. 



Mucus is a viscid, glairy stringy nitrogenous fluid. The 

 principal ingredient of mucus is mucin, a glucoproteid, although 

 there may also be present pseudomucins. Mucin imbibes water, 

 thus becoming swollen, and from this swollen mass there is pre- 

 cipitated a stringy material bv addition of alcohol or dilute acetic 

 arid. Pseudomucin forms a gelatinous mass when dissolved 

 in water, but by the addition of alcohol to this gelatinous mass 

 a stringv ])recipitate is formed which is redissolved in excess of 

 water, dift'ering in this respect from muciii. 



