FIB-SEM micrographs of a glomerular capillary wall. A and B: The glomerular filtration barrier using backscattered electron imaging (Additional file 12: Movie S6A). Labels: (C) capillary lumen, (IPS) interpodocyte space, (P) podocyte foot process, (GBM) glomerular basement membrane, (G) glycocalyx stained with LaDy GAGa, (F) fenestration and (S) slit diaphragm. C: A 3D surface image of the xyz stack (Scale Bar is 1 μm) (Additional file 13: Movie S6B). D: A set of stills through the glomerular filtration barrier (Approximately perpendicular to and indicated by dashed lines in 6A). i) Glycocalyx, ii) fenestrations, iii) glomerular basement membrane, iv) podocyte foot processes (Scale Bar is 500 nm).