[Changes in alpha-actinin localization and myofibrillogenesis in rat cardiomyocytes under cultivation].
By indirect immunofluorescence with monoclonal anti-alpha-actinin antibodies the localization of this contractile protein was studied in ventricular cardiac myocytes from newborn 2-4-day old rats in the course of their cultivation. In freshly isolated heart muscle cells a predominant longitudinal orientation of myofibrils was observed; in some cells on the periphery of cytoplasm the contours of Z-lines are indistinct. During cell spreading, in the areas of intercalated discs, growing processes were observed mostly containing no contractile structures at earlier stages of cultivation. On days 3 to 14, the cytoplasmic processes and ruffles are filled with developing myofibrils. The cultures are heterogeneous in the morphology of contractile apparatus of individual cells. In most cardiomyocytes mature myofibrils are well-developed in the central part of the cytoplasm, whereas in its peripheral areas non-myofibrillar stress-fiber-like structures and bundles with continuous distribution of alpha-actinin frequently connected to myofibrils are more typical. In the areas of active myofibrillogenesis, located mainly on the cell periphery, numerous alpha-actinin dots are observed; most of them are arranged linearly and periodically at a distance of 0.3-1.5 microns and seem to be structural precursors of Z-lines. The data obtained show that the cultures of mammalian cardiac cells may be a convenient object for studying myofibrillogenesis in the course of cardiomyogenic differentiation.
Borisov
A B
AB
Goncharova
E I
EI
Pinaev
G P
GP
Rumiantsev
P P
PP
D000185:Actinin / Q000276:immunology / Q000378:metabolism*; D000818:Animals; D000831:Animals, Newborn; D000911:Antibodies, Monoclonal; D002478:Cells, Cultured; D005455:Fluorescent Antibody Technique; D007150:Immunohistochemistry; D009206:Myocardium / Q000378:metabolism* / Q000648:ultrastructure; D009210:Myofibrils / Q000378:metabolism* / Q000648:ultrastructure; D051381:Rats
D000911:Antibodies, Monoclonal; D000185:Actinin
Izmeneniia lokalizatsii al'fa-aktinina i miofibrillogenez v kardiomiotsitakh krys pri kul'tivirovanii.