Bowen I D, Lewis G H, Winters C
Histochem J. 1983 Dec;15(12):1191-202. doi: 10.1007/BF01002739.
The role of atomic number contrast and backscattered imaging in the localization of histochemical products and reagents is reviewed. Particular attention is given to the localization of enzymatically released products. A backscattered imaging method is presented which permits the simultaneous demonstration of two label elements in a cryosection examined in the scanning electron microscope. An azo-dye method for the localization of acid phosphatase is combined with an autoradiographic technique for demonstrating [3H]thymidine incorporation. Atomic number contrast, produced by backscattered electrons, permits the detection of a bromine-labelled azo dye, denoting sites of acid phosphatase activity within a cryosection and the simultaneous display of the sites of the silver deposited in an overlying photographic emulsion. The former reveals acid phosphatase to be predominantly associated with thymocyte death and macrophage activity in mouse thymus. The latter pin-points the thymocytes as the main sites of [3H]thymidine incorporation. Atomic number contrast has a useful potential for differentiating between spatially separated histochemical products of differing atomic number in a structural context and also allows a flexible degree of subsurface localization.
本文综述了原子序数对比度和背散射成像在组织化学产物及试剂定位中的作用。特别关注酶促释放产物的定位。介绍了一种背散射成像方法，该方法可在扫描电子显微镜下对冷冻切片中的两种标记元素进行同步显示。一种用于酸性磷酸酶定位的偶氮染料法与一种用于显示[3H]胸腺嘧啶核苷掺入的放射自显影技术相结合。由背散射电子产生的原子序数对比度能够检测到溴标记的偶氮染料，从而在冷冻切片中指示酸性磷酸酶活性位点，并同时显示沉积在上覆照相乳剂中的银的位点。前者显示酸性磷酸酶主要与小鼠胸腺中的胸腺细胞死亡和巨噬细胞活性相关。后者则明确指出胸腺细胞是[3H]胸腺嘧啶核苷掺入的主要位点。原子序数对比度在区分结构背景中不同原子序数的空间分离组织化学产物方面具有有用的潜力，并且还允许进行灵活程度的亚表面定位。
