Sarcolemmal phospholamban is phosphorylated in isolated rat hearts perfused with isoprenaline.
Phosphorylation of phospholamban in cardiac sarcolemma is implicated in the increased influx of Ca2+ through the slow calcium channel induced by catecholamines. A method is described for the preparation of highly purified sarcolemmal vesicles from rat heart, and this has been used to examine the phosphorylation of phospholamban in 32Pi-perfused rat hearts. Phospholamban phosphorylation is increased 3-fold after 30 s of perfusion with 0.1 microM isoprenaline. The time course of this increase precedes the inotropic response by 5-10 s.
D000818:Animals; D002118:Calcium / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000378:metabolism*; D066298:In Vitro Techniques; D007473:Ion Channels / Q000378:metabolism*; D007545:Isoproterenol / Q000494:pharmacology*; D009206:Myocardium / Q000378:metabolism*; D010477:Perfusion; D010766:Phosphorylation; D051381:Rats; D012508:Sarcolemma / Q000378:metabolism*; D000099211:Phospholamban
D002118:Calcium; D002135:Calcium-Binding Proteins; D007473:Ion Channels; D007545:Isoproterenol; D000099211:Phospholamban