[Submicroscopic structure of collagen--a basis for the interpretation of corresponding polarization-optical and...

In view of new possibilities of acquiring relatively quantitative information about the molecular structure of collagenous fibres in histological section with the help of polarization and histochemical methods a survey is given of the most important aspects of the molecular structure of collagen in connection with the formation of "cross-links", giving due attention to the role of functional groups. These create the basis for interpreting morphological findings covering free amino-groups of lysin and hydroxylysin, guanidine groups of arginine and carboxyl groups of glutamic acid and asparaginic acid, gained by adding phenol or toluidine blue to collagenous fibres and by performing path difference measurements. References made to the applicability of this polarization-histochemical method in clinical research and diagnostics, in gathering reproducible data on processes of development or growth and aging and pathological changes in collagen are intended to encourage wide use of this examination technique in practice.