Polarization-optical investigation (topo-optical analysis) of the structure of the human erythrocyte glycocalyx. Influence of pH, ionic strength and diamide-induced spectrin cross linking.
The value of membrane anisotropy after fixation and topo-optical analysis of erythrocytes stained with toluidine blue is a measure for the degree of spatial order of the dyestuff-binding acidic residues of the glycocalyx and thus a parameter for the characterization of the glycocalyx structure. Lowering the pH value and/or the ionic strength of the staining medium results in a decrease of membrane anisotropy indicating a lower order of the anionic residues. In agreement with the findings of other authors this phenomenon seems to be connected with an expansion of the glycocalyx. Diamide-induced oxidative crosslinking of spectrin before fixation and staining with toluidine blue at physiological pH and ionic strength also results in a decreased anisotropy. This indirect influence on the glycocalyx structure may be caused by an increase of the charge density within the glycocalyx due to a diamide-induced rearrangement of the membrane skeleton and of the transmembrane proteins bound to it.
Halbhuber
K J
KJ
Department of Histochemistry, Friedrich Schiller University, Jena, GDR.
Oehring
H
H
Gliesing
M
M
Stibenz
D
D
D003958:Diamide; D004912:Erythrocytes / Q000737:chemistry*; D005454:Fluorescence Polarization; D006023:Glycoproteins / Q000032:analysis* / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D009994:Osmolar Concentration; D011134:Polysaccharides / Q000032:analysis* / Q000737:chemistry; D012794:Sialic Acids / Q000032:analysis; D013049:Spectrin / Q000737:chemistry*; D014048:Tolonium Chloride
D006023:Glycoproteins; D011134:Polysaccharides; D012794:Sialic Acids; D003958:Diamide; D013049:Spectrin; D014048:Tolonium Chloride