Neuringer J R, Clark J I, Benedek G B
Anat Rec. 1985 Mar;211(3):329-37. doi: 10.1002/ar.1092110315.
The outer cortical cells in the calf lens remain transparent under conditions that produce opacity in central nuclear cells. The nuclear cells opacify by a mechanism of cellular restructuring that is associated with a cytoplasmic phase separation while cortical cells do not opacify by this mechanism. In this study the differences in elemental composition of nuclear and cortical cells were analyzed using X-ray emission spectroscopy (XES) of tissue that was prepared for scanning electron microscopy. It was necessary to develop special methods of fixation and dehydration to prevent significant distortion of lens tissue and minimize solubilization and redistribution of elements during the histological processing of the tissue. We calibrated the microprobe for the quantitative analysis using gelatin standards which contained known concentrations of sulfur, potassium, phosphorus, chlorine, and cesium. The standard curves were used to determine proportionality constants, which related the intensity of X-ray emission to the molar concentration of each element, and to determine the minimum detectable levels of each element. An important finding is that the intensity of the X-ray emission is dependent on sample density only at low protein concentration. At the high protein concentrations that exist in lens, the intensity is not affected by sample density.(ABSTRACT TRUNCATED AT 250 WORDS)
小牛晶状体的外层皮质细胞在能使中央核细胞产生混浊的条件下仍保持透明。核细胞通过与细胞质相分离相关的细胞重组机制发生混浊，而皮质细胞不会通过这种机制发生混浊。在本研究中，使用为扫描电子显微镜制备的组织的X射线发射光谱（XES）分析了核细胞和皮质细胞的元素组成差异。有必要开发特殊的固定和脱水方法，以防止晶状体组织出现明显变形，并在组织的组织学处理过程中尽量减少元素的溶解和重新分布。我们使用含有已知浓度的硫、钾、磷、氯和铯的明胶标准品对微探针进行校准以进行定量分析。标准曲线用于确定比例常数，该常数将X射线发射强度与每种元素的摩尔浓度相关联，并确定每种元素的最低可检测水平。一个重要发现是，仅在低蛋白质浓度下，X射线发射强度才取决于样品密度。在晶状体中存在的高蛋白质浓度下，强度不受样品密度的影响。（摘要截短于250字）
