title: Heterogeneous localization of adenylate and guanylate cyclases in R3230AC rat mammary adenocarcinoma cells.
abstract: Adenylate and guanylate cyclase activities were demonstrated in R3230AC rat mammary adenocarcinomas by electron microscopic cytochemistry. Adenylate (AC) and guanylate (GC) cyclases were detected on plasma membrane of tumor epithelial cells, but not on fibroblasts and endothelial cells in the perivascular space. Both AC and GC activities were enriched in tumor epithelial cells at the periphery of the tumor lobular parenchyma rather than in cells in central core of the lobular parenchyma. Furthermore, the tumor cell plasma membranes facing the connective tissue stroma were in paucity or devoid of either enzyme activity. These heterogeneous distributions of both AC and GC among tumor epithelia suggest that R3230AC epithelial cells in different parts of the tumor mass may vary significantly in their regulation of cellular physiology.
authors.forename: B H
authors.initials: BH
authors.lastname: Hwang
authors.forename: D K
authors.initials: DK
authors.lastname: Liu
mesh_terms: D000230:Adenocarcinoma / Q000201:enzymology* / Q000648:ultrastructure; D000262:Adenylyl Cyclases / Q000032:analysis*; D000818:Animals; D002460:Cell Line; D005260:Female; D006162:Guanylate Cyclase / Q000032:analysis*; D006651:Histocytochemistry; D008325:Mammary Neoplasms, Experimental / Q000201:enzymology* / Q000648:ultrastructure; D008854:Microscopy, Electron; D051381:Rats
chemical_list: D000262:Adenylyl Cyclases; D006162:Guanylate Cyclase