Találati lista | Tudóstér

001-es BibID:	BIBFORM001041
Első szerző:	Jung, Carole
Cím:	Ca2+ release from the sarcoplasmic reticulum activated by the low affinity Ca2+ chelator TPEN in ventricular myocytes / Jung C., Zima A.V., Szentesi P., Jóna I., Blatter L.A., Niggli E.
Dátum:	2007
ISSN:	0143-4160 (Print)
Megjegyzések:	The Ca2+ content of the sarcoplasmic reticulum (SR) of cardiac myocytes is thought to play a role in the regulation and termination of SR Ca2+ release through the ryanodine receptors (RyRs). Experimentally altering the amount of Ca2+ within the SR with the membrane-permeant low affinity Ca2+ chelator TPEN could improve our understanding of the mechanism(s) by which SR Ca2+ content and SR Ca2+ depletion can influence Ca2+ release sensitivity and termination. We applied laser-scanning confocal microscopy to examine SR Ca2+ release in freshly isolated ventricular myocytes loaded with fluo-3, while simultaneously recording membrane currents using the whole-cell patch-clamp technique. Following application of TPEN, local spontaneous Ca2+ releases increased in frequency and developed into cell-wide Ca2+ waves. SR Ca2+ load after TPEN application was found to be reduced to about 60% of control. Isolated cardiac RyRs reconstituted into lipid bilayers exhibited a two-fold increase of their open probability. At the low concentration used (20-40microTPEN did not significantly inhibit the SR-Ca2+-ATPase in SR vesicles. These results indicate that TPEN, traditionally used as a low affinity Ca2+ chelator in intracellular Ca2+ stores, may also act directly on the RyRs inducing an increase in their open probability. This in turn results in an increased Ca2+ leak from the SR leading to its Ca2+ depletion. Lowering of SR Ca2+ content may be a mechanism underlying the recently reported cardioprotective and antiarrhythmic features of TPEN.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Cell Calcium. - 41 : 2 (2007), p. 187-194. -
További szerzők:	Zima, A.V. Blatter, L.A. Niggli, Ernst Szentesi Péter (1967-) (élettanász) Jóna István (1948-) (élettanász, fizikus)
Internet cím:	elektronikus változat elektronikus változat DOI
Borító:
Saját polcon:

001-es BibID:	BIBFORM078604
035-os BibID:	(WOS)000469204700012 (Scopus)85064219867
Első szerző:	Kutchukian, Candice
Cím:	Ca2+-induced sarcoplasmic reticulum Ca2+ release in myotubularin-deficient muscle fibers / Candice Kutchukian, Peter Szentesi, Bruno Allard, Anna Buj-Bello, Laszlo Csernoch, Vincent Jacquemond
Dátum:	2019
ISSN:	0143-4160
Megjegyzések:	Skeletal muscle deficiency in the 3-phosphoinositide (PtdInsP) phosphatase myotubularin (MTM1) causes myotubular myopathy which is associated with severe depression of voltage-activated sarcoplasmic reticulum Ca2+ release through ryanodine receptors. In the present study we aimed at further understanding how Ca2+ release is altered in MTM1-deficient muscle fibers, at rest and during activation. While in wild-type muscle fibers, SR Ca2+ release exhibits fast stereotyped kinetics of activation and decay throughout the voltage range of activation, Ca2+ release in MTM1-deficient muscle fibers exhibits slow and unconventional kinetics at intermediate voltages, suggestive of partial loss of the normal control of ryanodine receptor Ca2+ channel activity. In addition, the diseased muscle fibers at rest exhibit spontaneous elementary Ca2+ release events at a frequency 30 times greater than that of control fibers. Eighty percent of the events have spatiotemporal properties of archetypal Ca2+ sparks while the rest take either the form of lower amplitude, longer duration Ca2+ release events or of a combination thereof. The events occur at preferred locations in the fibers, indicating spatially uneven distribution of the parameters determining spontaneous ryanodine receptor 1 opening. Spatially large Ca2+ release sources were obviously involved in some of these events, suggesting that opening of ryanodine receptors in one cluster can activate opening of ryanodine receptors in a neighboring one. Overall results demonstrate that opening of Ca2+-activated ryanodine receptors is promoted both at rest and during excitation-contraction coupling in MTM1-deficient muscle fibers. Because access to this activation mode is denied to ryanodine receptors in healthy skeletal muscle, this may play an important role in the associated disease situation.
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban folyóiratcikk Skeletal muscle Ryanodine receptor Sarcoplasmic reticulum Ca2+ release Myotubular myopathy
Megjelenés:	Cell Calcium. - 80 (2019), p. 91-100. -
További szerzők:	Szentesi Péter (1967-) (élettanász) Allard, Bruno Buj-Bello, Anna Csernoch László (1961-) (élettanász) Jacquemond, Vincent
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Saját polcon:

001-es BibID:	BIBFORM011459
Első szerző:	Sztretye Mónika (élettanász, elektrofiziológus)
Cím:	Altered sarcoplasmic reticulum calcium transport in the presence of the heavy metal chelator TPEN / Sztretye M., Almássy J., Deli T., Szentesi P., Jung C., Dienes B., Simut C. A., Niggli E., Jona I., Csernoch L.
Dátum:	2009
Tárgyszavak:	Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Cell Calcium. - 46 : 5-6 (2009), p. 347-355. -
További szerzők:	Almássy János (1981-) (élettanász, biológus, angol-magyar szakfordító) Deli Tamás (1979-) (szülész-nőgyógyász, endokrinológus szakorvos) Szentesi Péter (1967-) (élettanász) Jung, Carole Dienes Beatrix (1972-) (élettanász, molekuláris biológus) Simut, Cecilia Niggli, Ernst Jóna István (1948-) (élettanász, fizikus) Csernoch László (1961-) (élettanász)
Internet cím:	Intézményi repozitóriumban (DEA) tárolt változat DOI
Borító:
Saját polcon: