Cytochemistry

Cytochemical methods for studying cellular and subcellular structures (organelles) of living organisms were first used by the French scientist Laurent in 1846, thereby opening the way for cytochemical studies of various cellular life forms. In those days, the main materials were muscles, nerve endings and visual cells of fish. The great importance of cytochemistry was associated with the possibility of studying the structure of nerve fibers and nerve endings. The rich experience in obtaining histological preparations was especially valuable for specialists of that time. In addition, it was possible to observe changes in the life cycle from division to degeneration in one individual. A special reagent was also developed - Schrage-Petersen trichrome, which can be used to detect azurophilic granules and other structural details. Among domestic cytologists, A. N. Filaretov was an active supporter and promoter of the use of cytochemical methods. It was he who first attracted the attention of I. P. Pavlov’s laboratory to the use in experiments of the school of Moscow physiologists of the two dyes described by Laurent, thanks to which morphological approaches to the study of the central mechanisms of nervous activity became available. This period of research is characterized by the development of intracorporeal microscopy, the study of the phenomenon of short-term local inhibition of nerve centers, voluntary and involuntary movements, analysis of the functioning of neurons in response to electrical signals, etc. Along with the study of nervous tissues using modern physicochemical research methods, cytochemical methods were also used. The reaction with alizarin red and Giemsa dye made it possible to study the features of myelination and axonal structures. Subsequently, this method was used to prepare multicolor sections of the brain (K. E. Fabry), which made it possible to identify many microorganisms