Light and electron microscopic demonstration of cholesterol distribution in membrane structures of the rat auditory...

As part of our investigations on the changes in the cortex of different stages of ontogeny, the aim of this study was to analyse the cholesterol distribution in the auditory cortex of adult rats. The light microscopic Schultz reaction as well as electron microscopic thin sections and freeze-etching combined with a cholesterol specific marker were applied to cholesterol demonstration. High and low cholesterol areas were found in the plasma membrane and membranes of some organelles. A low cholesterol content was observed in the membranes of the Golgi apparatus, mitochondria and junctional contacts. A very low cholesterol content was found in the pre- and postsynaptic membranes. High cholesterol contents were present in the neuronal and glial non-junctional plasma membranes. The cholesterol distribution in the membranes of the endoplasmic reticulum and nuclear envelope appeared to be different.