Abstract
The specific characterization of lipids was investigated by lysochromes* on routine semithin sections of osmium fixed tissues embedded in epon 812 for ultrastructural study. The work was done on trout and rat intestine during fat absorption. The best results were obtained after prefixation with paraformaldehyde.
1-1.5μm sections were stained by Sudan black B and Nile blue sulphate under well defined conditions. The use of H2O2 makes staining by lysochromes possible because: (i)-it eliminates the primary blackness due to osmium fixation and allows the visualisation of lysochromes which are dissolved in the lipids; (ii)-it increases the porosity of resin and allows the excess of lysochromes into the tissue lipids. The results obtained with Nile blue sulphate (colouring blue and red lysochrome) are discussed. A counterstaining with Ehrlich hematoxylin can be performed for later morphological study.
A further ultrastructural study allowed the identification of stained structures by Sudan black B and Nile blue sulphate.
