title: Characterization of the crude membrane fraction of cardiomyocytes using enzyme cytochemical markers.
abstract: The crude membrane fraction of cardiomyocytes, which had been used as the antigen for the study of autoantibodies against beta-adrenergic receptors, was characterized using cytochemical methods: in a reaction for adenylate cyclase as an enzyme marker of the beta-receptors of plasma membrane and in a reaction for glucose-6-phosphatase as an enzyme marker of the sarcoplasmic reticulum. The specific precipitates of both enzyme reactions were localized on the membrane vesicles. In case of AC reaction the precipitate was observed on approximately 80% and in case of G-6-Pase on approximately 25% of the whole amount of the vesicles observed, indicating prevalence of vesicles of plasmalemmal origin. These results reveal that the used membrane fraction is appropriate for the study of autoantibodies against beta-receptors, but it can also contain other proteins (antigens) which can cross-react with autoantibodies against beta-adrenergic receptors.
authors.affiliation: Institute for Heart Research, Slovak Academy of Sciences, Bratislava.
authors.forename: L
authors.initials: L
authors.lastname: Okruhlicová
authors.forename: N
authors.initials: N
authors.lastname: Tribulová
mesh_terms: D000262:Adenylyl Cyclases / Q000032:analysis*; D000818:Animals; D001323:Autoantibodies / Q000032:analysis; D002462:Cell Membrane / Q000737:chemistry / Q000201:enzymology*; D004285:Dogs; D005952:Glucose-6-Phosphatase / Q000032:analysis*; D006651:Histocytochemistry; D009206:Myocardium / Q000737:chemistry / Q000201:enzymology*; D011943:Receptors, Adrenergic, beta / Q000032:analysis / Q000276:immunology; D012519:Sarcoplasmic Reticulum / Q000201:enzymology
chemical_list: D001323:Autoantibodies; D011943:Receptors, Adrenergic, beta; D005952:Glucose-6-Phosphatase; D000262:Adenylyl Cyclases