Sarcoplasmic reticulum Ca2+ release in neonatal rat cardiac myocytes.

In the neonatal mammalian heart, the role of ryanodine receptor (=Ca(2+) release channel)-mediated sarcoplasmic reticulum (SR) Ca(2+) release for excitation-contraction coupling is still a matter of debate. Using an adenoviral system, we overexpressed separately the junctional SR proteins triadin, junctin, and calsequestrin, which are probably involved in regulation of ryanodine receptor function. Infection of neonatal rat cardiac myocytes with triadin, junctin, or calsequestrin viruses, controlled by green fluorescent protein expression, resulted in an increased protein level of the corresponding transgenes. Measurement of Ca(2+) transients of infected cardiac myocytes revealed unchanged peak amplitudes under basal conditions but with overexpression of calsequestrin and triadin caffeine-releasable SR Ca(2+) content was increased. Our results demonstrate that an increased expression of triadin or calsequestrin is associated with an increased SR Ca(2+) storage but unchanged Ca(2+) signaling in neonatal rat cardiac myocytes. This is consistent with an ancillary role of the sarcoplasmic reticulum in excitation-contraction coupling in the developing mammalian heart.

Gergs U ，Kirchhefer U ，Buskase J ，Kiele-Dunsche K ，Buchwalow IB ，Jones LR ，Schmitz W ，Traub O ，Neumann J ... -  《-》

Overexpression of junctin causes adaptive changes in cardiac myocyte Ca(2+) signaling.

Kirchhefer U ，Hanske G ，Jones LR ，Justus I ，Kaestner L ，Lipp P ，Schmitz W ，Neumann J ... -  《CELL CALCIUM》

Triadin overexpression stimulates excitation-contraction coupling and increases predisposition to cellular arrhythmia in cardiac myocytes.

Terentyev D ，Cala SE ，Houle TD ，Viatchenko-Karpinski S ，Gyorke I ，Terentyeva R ，Williams SC ，Gyorke S ... -  《-》

Modulation of SR Ca2+ release by the triadin-to-calsequestrin ratio in ventricular myocytes.

Kučerová D ，Baba HA ，Bokník P ，Fabritz L ，Heinick A ，Mát'uš M ，Müller FU ，Neumann J ，Schmitz W ，Kirchhefer U ... -  《-》

Transgenic triadin 1 overexpression alters SR Ca2+ handling and leads to a blunted contractile response to beta-adrenergic agonists.

Kirchhefer U ，Jones LR ，Begrow F ，Boknik P ，Hein L ，Lohse MJ ，Riemann B ，Schmitz W ，Stypmann J ，Neumann J ... -  《CARDIOVASCULAR RESEARCH》