Abstract
Small cell tumors, liver and skin biopsies for metabolic disorders, soft tissue tumors and kidney biopsies are the paraffin embedded tissues most frequently requested for ultrastructural examination. Preservation of cell membranes, glycogen, mucopolysaccharides, glycoproteins, glycolipids and other soluble components is problematic in these cases. Causes of cellular extraction when processing paraffin embedded tissue are:a) inadequate fixation of carbohydrates, mucopolysaccarides, glycoproteins and glycolipidsb) extraction of lipids and cell membranes by polar solventsc) temperature effectsd) extraction of sugars and glycoproteins due to pH and non-buffered, hypo-osmolar solutions.A methodology which improves preservation is described below:1) Tissue samples are cut from paraffin blocks and deparaffinized in 2 changes of xylene at 4°C for 2-4 h (low temperature decreases extraction in solvent).2) The samples are then rehydrated through a decreasing series of acetone concentrations (5-10 min each) at 4°C to 2, 5-10 min changes of 0.1 M cacodylate buffer containing 14.4 mM sucrose and 3.5 mM CaCl2, pH 7.8 (less polar solvent -- acetone vs. ethanol -- should decrease lipid extraction thereby enhancing membrane preservation)
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Proceedings, annual meeting, Electron Microscopy Society of America
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
