[ATP-dependent transport of Ca2+ in myocardium sarcolemma vesicles and its activation by phorbol esters].
Highly purified pig myocardium sarcolemma vesicles possess the Ca2+,Mg2+-ATPase activity (4.1 mumol Pi/mg protein/hour) and induce the ATP-dependent accumulation of 45Ca2+ (6.0 nmol/mg protein/min). This reaction is not stimulated by oxalate; Ca2+ are released from the vesicles by saponin and Na+ treatment, which suggests that Ca2+ transport against the concentration gradient is induced by myocardium sarcolemma vesicles and not by sarcoplasmic reticulum fragments. The phorbol ester possessing a biological activity of a growth-promoting factor and activating membrane-bound protein kinase C stimulates the Ca2+,Mg2+-ATPase activity and the ATP-dependent accumulation of Ca2+, whereas its counterpart devoid of biological activity does not influence Ca2+ transport. Polymixin B, a specific inhibitor of protein kinase C, prevents the activating effect of phorbol esters on Ca2+ accumulation inside the vesicles. It is suggested that the ATP-dependent transport of Ca2+ in myocardium sarcolemma is controlled by Ca2+-phospholipid-dependent phosphorylation catalyzed by protein kinase C.
Kurskiĭ
M D
MD
Kocherga
V I
VI
Nesterenko
N V
NV
Vorobets
Z D
ZD
Kurchenko
L K
LK
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D017301:Ca(2+) Mg(2+)-ATPase / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000378:metabolism; D066298:In Vitro Techniques; D009206:Myocardium / Q000201:enzymology / Q000378:metabolism*; D010703:Phorbol Esters / Q000494:pharmacology*; D012508:Sarcolemma / Q000201:enzymology / Q000378:metabolism*; D013552:Swine
D010703:Phorbol Esters; D000255:Adenosine Triphosphate; D017301:Ca(2+) Mg(2+)-ATPase; D000252:Calcium-Transporting ATPases; D002118:Calcium
ATP-zavisimyĭ transport Ca2+ vezikulirovannymi preparatami sarkolemmymiokarda i ego aktivatsiia forbolovymi éfirami.