Leone B E, Taccagni G L, Dell'Antonio G, Cantaboni A
Cattedra di Anatomia, Università degli Studi di Milano, Italy.
Basic Appl Histochem. 1990;34(2):143-53.
The ultrastructural localization of chromogranin A (Chr A) was studied in eleven neoplasias of the diffuse neuroendocrine system (3 pancreatic islet-cell tumours, 1 medullary carcinoma of the thyroid, 1 large bowel and 1 small bowel carcinoid tumours, 2 carcinoid tumours of the lung, 1 adenoma of the parathyroid gland, 2 pheochromocytomas of the adrenal gland). On account of the great influence of the technical treatment of the samples on the immunolocalization of Chr A, the effect of the following variables was studied in a case of pheochromocytoma: fixation in glutaraldehyde versus paraformaldehyde, postfixation in osmium tetroxide versus omission, embedding in epoxy resin versus acrylic resin. The method of choice for the better preservation of the antigenic character of the tissue was found to be fixation in 4% paraformaldehyde, omission of osmium postfixation and embedding in LRWhite acrylic resin; by this procedure we were able to find Chr A in the neurosecretory granules of all the studied cases, using three commercially available antibodies directed against Chr A. These findings further confirm that Chr A is a reliable marker for the study of neuroendocrine neoplasias by electron microscopy.
研究了嗜铬粒蛋白A（Chr A）在11例弥漫性神经内分泌系统肿瘤中的超微结构定位（3例胰岛细胞瘤、1例甲状腺髓样癌、1例大肠类癌和1例小肠类癌、2例肺类癌、1例甲状旁腺腺瘤、2例肾上腺嗜铬细胞瘤）。由于样本的技术处理对Chr A免疫定位有很大影响，在1例嗜铬细胞瘤中研究了以下变量的作用：戊二醛固定与多聚甲醛固定、四氧化锇后固定与不进行后固定、环氧树脂包埋与丙烯酸树脂包埋。结果发现，更好地保存组织抗原特性的首选方法是用4%多聚甲醛固定、不进行四氧化锇后固定并采用LRWhite丙烯酸树脂包埋；通过该程序，使用三种市售的抗Chr A抗体，我们在所有研究病例的神经分泌颗粒中均发现了Chr A。这些发现进一步证实，Chr A是通过电子显微镜研究神经内分泌肿瘤的可靠标志物。
