In the renal glomerulus, the narrow slits between adjacent epithelial podocytes are bridged by a diaphragm (2, 8, 11). In rat and mouse kidneys fixed by perfusion with tannic acid and glutaraldehyde (TAG), it has recently been discovered that this diaphragm has a highly ordered, isoporous substructure (9). It consists of a regular array of alternating cross bridges extending from the podocyte plasma membranes to a centrally running filament. This zipperlike pattern results in two rows of rectangular pores, approximately 40 X 140 A in cross section, dimensions consistent with the proposed role of the diaphragm as an important filtration barrier to plasma proteins (6). In the present study, we found in freeze-cleaved and in freeze-etched normal rat glomeruli that the surface of the slit diaphragm has an appearance conforming to the pattern found in sectioned material.
Article| April 01 1975
Substructure of the glomerular slit diaphragm in freeze-fractured normal rat kidney
Online ISSN: 1540-8140
Print ISSN: 0021-9525
J Cell Biol (1975) 65 (1): 233–236.
MJ Karnovsky, GB Ryan; Substructure of the glomerular slit diaphragm in freeze-fractured normal rat kidney . J Cell Biol 1 April 1975; 65 (1): 233–236. doi: https://doi.org/10.1083/jcb.65.1.233
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