Hearn S A
J Histochem Cytochem. 1987 Jul;35(7):795-801. doi: 10.1177/35.7.3295032.
An antibody (LK2H10) to chromogranin A has been recommended for use in ultrastructural identification of neuroendocrine secretory granules. Previous studies have demonstrated immunoreactive chromogranin A in specimens prepared for electron microscopy by glutaraldehyde fixation only. In this study, the effect of specimen post-fixation by osmium tetroxide on post-embedding localization of chromogranin A was evaluated. Human tissues from benign endocrine glands, neuroendocrine tumors, and non-neuroendocrine tumors were post-fixed in osmium, embedded in epoxy resin, and the sample thin sections immunolabeled using a protein A-gold technique. Chromogranin A-positive neurosecretory granules were detected in pancreatic islets, adrenal medulla, stomach, ileum, anterior pituitary, and parathyroid. Mid-gut carcinoids, bronchial carcinoids, pheochromocytomas, paragangliomas, carotid body tumors, and thyroid medullary carcinomas contained immunoreactive granules. Cytoplasmic granules in non-neuroendocrine tumors did not react for chromogranin A. Tissues post-fixed in osmium tetroxide had optimally preserved ultrastructural features, and use of this fixative is compatible with postembedding localization of chromogranin A in neurosecretory granules.
一种针对嗜铬粒蛋白A的抗体（LK2H10）已被推荐用于神经内分泌分泌颗粒的超微结构鉴定。先前的研究仅在通过戊二醛固定制备用于电子显微镜检查的标本中证实了免疫反应性嗜铬粒蛋白A。在本研究中，评估了四氧化锇对标本进行后固定对嗜铬粒蛋白A包埋后定位的影响。取自良性内分泌腺、神经内分泌肿瘤和非神经内分泌肿瘤的人体组织用锇进行后固定，包埋在环氧树脂中，然后使用蛋白A-金技术对样品薄片进行免疫标记。在胰岛、肾上腺髓质、胃、回肠、垂体前叶和甲状旁腺中检测到嗜铬粒蛋白A阳性神经分泌颗粒。中肠类癌、支气管类癌、嗜铬细胞瘤、副神经节瘤、颈动脉体瘤和甲状腺髓样癌含有免疫反应性颗粒。非神经内分泌肿瘤中的细胞质颗粒对嗜铬粒蛋白A无反应。用四氧化锇进行后固定的组织具有最佳保存的超微结构特征，并且使用这种固定剂与嗜铬粒蛋白A在神经分泌颗粒中的包埋后定位兼容。
