Zaar K, Fahimi H D
Department of Anatomy and Cell Biology, University of Heidelberg, Federal Republic of Germany.
Cell Tissue Res. 1990 May;260(2):409-14. doi: 10.1007/BF00318644.
The ultrastructure of peroxisomes in the proximal nephron tubules of bovine kidney cortex was studied using ultrathin-sectioning, diaminobenzidine cytochemistry for the visualization of catalase, and by freeze-fracture. Peroxisomes in this nephron segment are up to 1.5 microns in diameter and exhibit a peculiar angular shape, which is probably related to the occurrence of multiple straight plate-like inclusions (marginal plates) in the matrix of peroxisomes; they lie directly underneath the peroxisomal membranes. The peroxisomal membrane in such regions follows the outline of the marginal plate. The peculiar shape of peroxisomes allows their unequivocal identification in freeze-fracture preparations. Peroxisomal membranes are recognized by their flat, often rectangular appearance. Intramembrane particles are much more numerous on P-fracture faces than on E-fracture faces. A crystalline lattice-structure with a periodicity of approximately 10 nm can be observed on the flat rectangular areas of E-fracture faces. This lattice structure is intensified after prolonged freeze-etching. Intramembranous particles seem to be superimposed over this pattern. The crystalline pattern on the E-fracture faces of peroxisomal membranes is probably not a membrane structure but it reveals the structure of the membrane-associated marginal plates. A cast of the marginal-plate surface may be generated by a collapse of the peroxisomal membrane half onto the immediately underlying matrix inclusion.
利用超薄切片、二氨基联苯胺细胞化学法以显示过氧化氢酶以及冷冻断裂技术，对牛肾皮质近端肾小管中过氧化物酶体的超微结构进行了研究。该肾单位节段中的过氧化物酶体直径可达1.5微米，呈现出一种奇特的角状形态，这可能与过氧化物酶体基质中多个直的板状内含物（边缘板）的存在有关；它们直接位于过氧化物酶体膜下方。此类区域的过氧化物酶体膜沿着边缘板的轮廓延伸。过氧化物酶体的奇特形态使其在冷冻断裂标本中易于明确识别。过氧化物酶体膜以其扁平、通常呈矩形的外观而被识别。内膜颗粒在P面断裂面上比在E面断裂面上要多得多。在E面断裂面的扁平矩形区域可观察到一种周期约为10纳米的晶格结构。经过长时间冷冻蚀刻后，这种晶格结构会增强。内膜颗粒似乎叠加在这种模式之上。过氧化物酶体膜E面断裂面上的晶体模式可能不是一种膜结构，而是揭示了与膜相关的边缘板的结构。过氧化物酶体膜的一半塌陷到紧邻其下的基质内含物上，可能会形成边缘板表面的铸型。
