title: Creatine kinase isozyme expression in prenatal rat heart.
abstract: The distribution pattern of creatine kinase (E.C 2.7.3.2) isozymes in prenatal rat heart and skeletal muscle was studied by immunohistochemistry. Between embryonic day (ED) 12-18, creatine kinase M (CK-M) is heterogeneously expressed in the heart: a pronounced staining of CK-M is first observed in the outflow tract and the trabeculae of the right ventricle (ED12-14), and subsequently in the venous valves, the interatrial septum and the sinoatrial node. From ED18 onwards, a homogeneous expression of CK-M is observed due to an increase in isozyme concentration in the remaining part of the myocardium. By contrast, the developmental appearance of creatine kinase B (CK-B) occurs almost homogeneously throughout the heart between ED11-14. Thereafter, a decrease of the CK-B is first observed in the inflow tract (in particular in the sinoatrial node), in the inner part of those atrial walls that are adjacent to the atrioventricular junction, and temporarily in a band in the upper part of the interventricular septum. From ED18, a selective disappearance of CK-B is found in the papillary muscle of the left ventricle. At birth, a considerable amount of CK-B remains present in the ventricular walls. Although some of the stage-dependent regional differences in expression of the creatine kinase isozymes, in particular those of the M-subunit, are shared by other mammalian and avian species, their significance for the developmental changes in the physiology of the heart is speculative at present.
authors: Department of Anatomy and Embryology, University of Amsterdam, The Netherlands.
authors: H D
authors: HD
authors: Hasselbaink
authors: W T
authors: WT
authors: Labruyère
authors: A F
authors: AF
authors: Moorman
authors: W H
authors: WH
authors: Lamers
mesh_terms: D000818:Animals; D000918:Antibody Specificity; D015153:Blotting, Western; D003402:Creatine Kinase / Q000096:biosynthesis* / Q000276:immunology; D005404:Fixatives / Q000494:pharmacology; D015870:Gene Expression; D007150:Immunohistochemistry; D007527:Isoenzymes; D009132:Muscles / Q000378:metabolism; D009206:Myocardium / Q000201:enzymology*; D051381:Rats; D011919:Rats, Inbred Strains / Q000196:embryology*
chemical_list: D005404:Fixatives; D007527:Isoenzymes; D003402:Creatine Kinase