A morphological and biochemical study of myelinogenesis in fish brain

Myelinogenesis in different brain parts of trout was studied comparatively by means of histochemistry and biochemistry. A more detailed approach, including ultrastructural analysis, to characterize this important differentiation process, particularly in the optic tectum, revealed a good correlation between the structural development of myelinated axons and the lipid composition of membranes. The molar ratio of cholesterol to phospholipids and galactolipids proved to be most suitable for monitoring myelination in fish CNS.