title: Fluorescence histochemistry of RNA in human pituitary adenomas.
abstract: Acridine orange (AO)-RNA fluorescence was studied histochemically in 9 normal human pituitary glands, in 26 secretory and nonsecretory pituitary adenomas, and in a dysgerminoma. Six adenomas showing immunoreactivity for prolactin showed intense orange-red cytoplasmic fluorescence; 6 other tumours exhibiting immunoperoxidase activity of growth hormone showed less intense AO-RNA fluorescence, and 5 adrenocorticotropic hormone-containing adenomas showed still weaker orange fluorescence. Among the chromophobe adenomas without immunoreactivity for secretory products, 5 had uniformly very weak AO-RNA fluorescence, while in 4 other a few scattered cells with strong AO-RNA fluorescence were detected among the majority of weakly fluorescent cells. The pituitary dysgerminoma contained many cells with strong AO-RNA fluorescence. Electron microscopy of these cases showed good correlation of cytoplasmic concentration of ribosomes with AO-RNA fluorescence of the adenomas. AO is useful as an inexpensive, simple supplementary stain for frozen or paraffin sections of pituitary tumours to infer secretory activity as a correlate of RNA concentration and to demonstrate a secretory potential in some cells of hormonally inactive tumours.
authors: Department of Pathology, University of Calgary Faculty of Medicine, Canada.
authors: H B
authors: HB
authors: Sarnat
authors: J H
authors: JH
authors: García
authors: B
authors: B
authors: Curry
mesh_terms: D000165:Acridine Orange; D000236:Adenoma / Q000378:metabolism* / Q000648:ultrastructure; D000238:Adenoma, Chromophobe / Q000378:metabolism / Q000648:ultrastructure; D004407:Dysgerminoma / Q000378:metabolism / Q000648:ultrastructure; D005453:Fluorescence; D006651:Histocytochemistry / Q000379:methods*; D007124:Immunoenzyme Techniques; D010903:Pituitary Gland, Anterior / Q000032:analysis; D010911:Pituitary Neoplasms / Q000378:metabolism* / Q000648:ultrastructure; D012313:RNA / Q000032:analysis*; D013194:Staining and Labeling
chemical_list: D012313:RNA; D000165:Acridine Orange