Integrated stereological and biochemical studies on hepatocytic membranes. II. Correction of section thickness effect on volume and surface density estimates
Integrated stereological and biochemical studies on hepatocytic membranes. II. Correction of section thickness effect on volume and surface density estimates
复制标题
肝细胞膜的综合体视学和生化研究。
DOI：
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发表时间：
1978
影响因子：
7.8
通讯作者：
D. Paumgartner
中科院分区：
文献类型：
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作者：
E. Weibel;D. Paumgartner
用于估算体积密度（Vv）和表面密度（Sv）的基本体视学公式仅对真正的无限薄切片严格有效;使用有限厚度T的“X”切片会引入系统误差，主要是在高估参数的意义上。这些误差取决于结构元件的尺寸和形状以及T。通过考虑模拟亚细胞器的形状和排列的模型结构，导出了T的这种效应的校正因子：（a）球形囊泡，（B）圆盘作为粗面内质网（RER）池的模型，（c）圆柱形小管作为光滑内质网（SER）小管、微绒毛等的模型。校正因子考虑了由于擦过部分和囊泡的尺寸分布引起的帽损失。圆盘模型和小管模型与R.E. Miles认为“互穿”颗粒的随机聚集体，使得所得结构是非凸的，因此在本质上近似内质网（ER）的网络特征。一些关于肝细胞的实际例子表明，由于切片厚度引起的误差可能在20-40%或更大的量级。给出了确定Vv和Sv修正系数的计算公式和图表。
The basic stereological formulas for estimating volume (Vv) and surface (Sv) densities are strictly valid only for true infinitely thin sections; the use of "ultrathin" sections of finite thickness T introduces systematic errors, mostly in the sense of overestimation of the parameters. These errors depend on the size and shape of the structural elements and on T. Correction factors for this effect of T are derived by considering model structures that simulate the shape and arrangement of subcellular organelles: (a) spherical vesicles, (b) disks as models for rough endoplasmic reticulum (RER) cisternae, (c) cylindrical tublules as models for smooth endoplasmic reticulum (SER) tubules, microvilli, etc. For vesicles, a model of discrete convex spherical particles is assumed; the correction factors consider loss of caps due to grazing sections and size distribution of the vesicles. The disk and tubule models are used in connection with the new integral geometric formulas of R.E. Miles which consider random aggregates of "inter-penetrating" particles so that the resultant structure is non- convex and thus approximates in nature the networks characteristic of endoplasmic reticulum (ER). Some practical examples relative to liver cells show that the errors due to section thickness may be of the order of 20-40% or more. Computation formulas as well as graphs are given for the determination of the correction factors for Vv and Sv.