title: Extraction of glycoproteins during tissue preparation for electron microscopy.
abstract: The extraction of glycoproteins labelled with 3H or 14C precursors: fucose and glucosamine, has been compared during processing of rat liver for transmission electron microscopy. Using 14C labelled fucose, approximately 6% of labelled macromolecules were extracted during processing including 3% during glutaraldehyde fixation, 1% during post-fixation and 2% during dehydration. Greater extraction (8%) occurs with glucosamine as a precursor, which may be attributed to hydrolysis of the more labile sialic acid residues of the glycoprotein molecules. Tritium labelled glycoproteins were more susceptible to extraction than 14C-labelled glycoproteins. The extraction of 3H-labelled glycoproteins as measured by liquid scintillation counting may prove difficult to interpret owing to the quenching from processing solutions.
mesh_terms: D000818:Animals; D002250:Carbon Radioisotopes; D005643:Fucose; D005944:Glucosamine; D006023:Glycoproteins / Q000302:isolation & purification*; D006652:Histological Techniques; D008099:Liver / Q000032:analysis*; D008297:Male; D008854:Microscopy, Electron / Q000379:methods; D051381:Rats; D014316:Tritium
chemical_list: D002250:Carbon Radioisotopes; D006023:Glycoproteins; D014316:Tritium; D005643:Fucose; D005944:Glucosamine