Karnovsky M J, Ryan G B
J Cell Biol. 1975 Apr;65(1):233-6. doi: 10.1083/jcb.65.1.233.
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.
在肾小球中，相邻上皮足细胞之间狭窄的裂隙由一层滤过膜连接（2, 8, 11）。最近发现，用鞣酸和戊二醛灌注固定的大鼠和小鼠肾脏（TAG）中，这种滤过膜具有高度有序的等孔亚结构（9）。它由从足细胞质膜延伸到中央细丝的交替排列的规则横桥阵列组成。这种拉链状模式形成了两排矩形孔隙，横截面约为40×140埃，其尺寸与滤过膜作为血浆蛋白重要滤过屏障的作用相符（6）。在本研究中，我们在冷冻断裂和冷冻蚀刻的正常大鼠肾小球中发现，裂隙滤过膜的表面外观与切片材料中发现的模式一致。
