alcian-blue and Glomerulonephritis--Membranous

Some preliminary observations suggest that predisposition to a particular type of glomerulonephritis (GN) may be connected with the genetically determined charge of the glomerular capillary wall. A correlation between erythrocyte surface and the glomerular capillary wall charges has also been observed. The purpose of this study was to verify and extend previous investigations. Therefore we measured erythrocyte and platelet surface charge from patients with idiopathic membranous and mesangial GN as well as idiopathic membranoproliferative GN and lupus nephritis.. The erythrocyte and platelet surface charge was determined by the binding of the cationic dye, alcian blue (AB). A fresh alcoholic AB solution was made for each experiment, which were run in batches of four, each including cells from a healthy person and from patients each with a different type of GN.. In patients with idiopathic membranous and membranoproliferative GN, a significant decrease in the erythrocyte and platelet charges was observed irrespective of their clinical state (remission or nephrotic syndrome). Erythrocyte charge was decreased despite the normal amount of membranous sialic acid. In contrast, patients with idiopathic mesangial GN, in complete or partial remission, exhibited normal erythrocyte and platelet surface charges. Exclusively in this type of GN, the appearance of nephrotic proteinuria was associated with a slight decrease, the erythrocyte charge, which was not statistically significant (P > 0.1). A reduction in the negative erythrocyte charge in lupus nephritis was less in magnitude than in idiopathic membranous or membranoproliferative GN, and occurred independently of the level of daily proteinuria, whereas the platelet charge was normal.. The decrease of the erythrocyte and platelet charge in idiopathic membranous and mebranoproliferative GN seems to be a pre-morbid feature.

Topics: Adolescent; Adult; Aged; Alcian Blue; Blood Platelets; Case-Control Studies; Cell Membrane; Coloring Agents; Electrochemistry; Erythrocyte Membrane; Female; Glomerulonephritis; Glomerulonephritis, Membranoproliferative; Glomerulonephritis, Membranous; Humans; Lupus Nephritis; Male; Membrane Potentials; Middle Aged; Nephrotic Syndrome; Proteinuria; Surface Properties

We studied direct and indirect methods of measuring membrane charge by detecting fixed anionic sites with polyethylenimine (PEI) on the glomerular basement membrane (GBM) and Alcian blue on red blood cell (RBC) membrane (ABRBC), respectively, in 40 children with nephrotic syndrome (NS). Size selectivity of the GBM was measured indirectly by fine analysis of urinary proteins with sodium dodecyl sulfate-polyacrylamide gel electrophoresis in 22 of these children. Correlation between ABRBC and PEI was strongest (r = 0.79; p = 0.0037) in 11 children with steroid-responsive NS (SRNS), moderate (r = 0.31) in 10 children with focal glomerulosclerosis (FGS), and absent in 14 children with hepatitis B antigen membranous nephropathy (MGN) and 5 with mesangioproliferative glomerulonephritis (MPGN). ABRBC and PEI were reduced in the group as a whole as compared with their controls (ABRBC: 44.53 +/- 9.81 vs 71.54 +/- 12.14, p < 0.05; PEI: 16.31 +/- 4.34 vs 33.3 +/- 1.09, p < 0.005). This reduction was greater in SRNS (26.35 +/- 7.15 p = 0.004) but was also detected in the remainder of the group taken together (52.31 +/- 26.07, p < 0.001). Excretion of glomerular proteins was restricted by size (< or = 80 kd) in SRNS but unrestricted (< or = 80 kd plus > 80 kd) in FGS, MGN, and MPGN. The main cause of proteinuria is likely to be depletion of negative charge on the GBM in SRNS, and distortion of capillary pore size in MGN and MPGN, with probable overlap of these mechanisms in each disease, especially in FGS. Basement membrane injury appears widespread in SRNS but confined to the kidney in MGN and MPGN.

Topics: Alcian Blue; Basement Membrane; Biopsy; Child; Child, Preschool; Erythrocyte Membrane; Glomerulonephritis, Membranous; Glomerulosclerosis, Focal Segmental; Hepatitis B; Humans; In Vitro Techniques; Kidney Glomerulus; Nephrotic Syndrome; Proteinuria