TOPOCHEMICAL REACTIONS 

 IN POLARIZATION MICROSCOPY 

 OF CONNECTIVE TISSUE 

 AND ITS INTERCELLULAR SUBSTANCES 



G. ROMHÂNYI 



(Pécs) 



Topochemical reactions (TR) provide a useful approach to the study of 

 the submicroscopic and chemical organisation of coUagen, elastic and 

 reticulin fibres, and connective tissue ground substance. 



In an optical sensé by TR are ment events in which uncoloured or 

 coloured compounds are associated in an orientated pattern on anisotropic 

 substrates enhancing or reversing their original biréfringence. 



The type and strength of binding of the associating components in TR 

 may vary from true chemical bonds to loose réversible adsorption. The 

 optical effect of anisotropic staining — often associated with anomalous 

 colours — can be markedly enhanced and stabilized by appropriate preci- 

 pitating agents used after staining and also in the mounting médium. 



It was possible to show that by différent TR (phenol-anilin reaction 

 and anisotropic toluidinblue staining) the elastic fibres of the aorta hâve 

 a fibrillary structure with a spiral arrangement of their submicroscopic 

 filaments, the degree of élévation of the helicoid being 45° in the elastic 

 fibres of young humans and about 20 to 25 degrees in the elastic fibres 

 of ox ligamentum nuchae. 



It was found that apart from their well known and characteristic phénol 

 reaction (Ebner) collagen fibres showed anisotropic staining with the 

 acridine dye rivanol becoming negatively biréfringent, which seems to be 

 a characteristic TR of the collagen fibres. 



Recently considérable attention has been paid to the structural and 

 functional significance of the AMP contained in the ground substance the 

 structural organization of which has not yet ben clarified unambiguously. 

 However, the fact that after anisotropic staining with appropriate basic 

 dyes below pH 4*0 collagen fibres, and also collagen fibrils precipitated 

 in vitro with CHS A, become negatively biréfringent can be related to the 

 AMP component contained in the fibres in an organized pattern. Further- 

 more, polarization optical findings suggest that metachromasia seen in 



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