CCL

Összesen 8 találat.
#/oldal:
Részletezés:
Rendezés:

1.

001-es BibID:BIBFORM030668
Első szerző:Ait Mou, Younss
Cím:Beneficial effects of SR33805 in failing myocardium / Ait Mou, Y., Toth, A., Cassan, C., Czuriga, D., de Tombe, P. P., Papp, Z., Lacampagne, A., Cazorla, O.
Dátum:2011
ISSN:0008-6363
Megjegyzések:Aims: SR33805, a potent Ca2+ channel blocker, increases cardiac myofilament Ca2+ sensitivity in healthy rat cardiomyocytes. Therefore, the aim of the present study was to evaluate the effects of SR33805 on contractile properties in ischaemic failing hearts after myocardial infarction (MI) in vivo and in vitro at the cellular level. Methods and results: The effect of SR33805 (10 mM) was tested on the excitation?contraction coupling of cardiomyocytes isolated from rat with end-stage heart failure. Cell shortening and Ca2+ transients were measured in intact cardiomyocytes, while contractile properties were determined in Triton X-100 permeabilized myocytes. Acute treatment with SR33805 restored the MI-altered cell shortening without affecting the Ca2+ transient amplitude, suggesting an increase of myofilament Ca2+ sensitivity in MI myocytes. Indeed, a SR33805-induced sensitization of myofilament activation was found to be associated with a slight increase in myosin light chain-2 phosphorylation and a more significant decrease on troponin I (TnI) phosphorylation. Decreased TnI phosphorylation was related to inhibition of protein kinase A activity by SR33805. Finally, administration of a single intra-peritoneal bolus of SR33805 (20 mg/kg) improved endsystolic strain and fractional shortening of MI hearts. Conclusion: The present study indicates that treatment with SR33805 improved contractility of ischaemic failing hearts after MI in the rat by selectively modulating the phosphorylation status of sarcomeric regulatory proteins, which then sensitized the myofilaments to Ca2+. Our results gave a proof of concept that manipulation of the Ca2+ sensitivity of sarcomeric regulatory proteins can be used to improve contractility of a failing heart.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Myocytes
Heart failure
Contractile function
Sarcomere
Ventricular function
Megjelenés:Cardiovascular Research. - 91 : 3 (2011), p. 412-419. -
További szerzők:Tóth Attila (1971-) (biológus) Cassan, Cécile Czuriga Dániel (1982-) (kardiológus) de Tombe, Pieter P. Papp Zoltán (1965-) (kardiológus, élettanász) Lacampagne, Alain Cazorla, Olivier
Pályázati támogatás:INSERM
Egyéb
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:

2.

001-es BibID:BIBFORM004074
Első szerző:Birinyi Péter (élettanász)
Cím:The Na+/Ca2+ exchange blocker SEA0400 fails to enhance cytosolic Ca2+ transient and contractility in canine ventricular cardiomyocytes / Birinyi P., Tóth A., Jóna I., Acsai K., Almássy J., Nagy N., Prorok J., Gherasim I., Papp Z., Hertelendi Z., Szentandrássy N., Bányász T., Fülöp F., Papp J. G., Varró A., Nánási P. P., Magyar J.
Dátum:2008
Megjegyzések:Aims This study was designed to evaluate the effects of the Na+/Ca2+ exchange (NCX) inhibitor SEA0400 on Ca2+ handling in isolated canine ventricular myocytes. Methods and results Intracellular Ca2+ ([Ca2+](i)) transients, induced by either field stimulation or caffeine flush, were monitored using Ca2+ indicator dyes. [Ca2+](i)-dependent modulation of the inhibitory effect of SEA0400 on NCX was characterized by the changes in Ni2+-sensitive current in voltage-clamped myocytes. Sarcoplasmic reticulum (SR) Ca2+ release and uptake were studied in SIR membrane vesicles. Gating properties of single-ryanodine receptors were analysed in lipid bilayers. Ca2+ sensitivity of the contractile machinery was evaluated in chemically skinned myocytes. In myocytes paced at 1 Hz, neither diastolic [Ca2+](i) nor the amplitude of [Ca2+](i) transients was significantly altered by SEA0400 up to the concentration of 1 mu M, which was shown to inhibit the exchange current. The blocking effect of SEA0400 on NCX decreased with increasing [Ca2+](i), and it was more pronounced in reverse than in forward mode operation at every [Ca2+](i) examined. The rate of decay of the caffeine-induced [Ca2+](i) transients was decreased significantly by 1 mu M SEA0400; however, this effect was only a fraction of that observed with 10 mM NiCl2. Neither SR Ca2+ release and uptake nor cell shortening and Ca2+ sensitivity of the contractile proteins were influenced by SEA0400. Conclusion The lack of any major SEA0400-induced shift in Ca2+ transients or contractility of myocytes can well be explained by its limited inhibitory effect on NCX (further attenuated by elevated [Ca2+](i) levels) and a concomitant reduction in Ca2+ influx due to the predominantly reverse mode blockade of NCX and suppression of L-type Ca2+ current.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Cardiovascular Research. - 78 : 3 (2008), p. 476-484. -
További szerzők:Tóth András (farmakológus) Jóna István (1948-) (élettanász, fizikus) Acsai Károly Almássy János (1981-) (élettanász, biológus, angol-magyar szakfordító) Nagy Norbert (1977-) (kísérletes farmakológus) Prorok János Gherasim, Iuliana Papp Zoltán (1965-) (kardiológus, élettanász) Hertelendi Zita (1978-) (orvos) Szentandrássy Norbert (1976-) (élettanász) Bányász Tamás (1960-) (élettanász) Fülöp Ferenc Papp Gy. Julius (Szeged) Varró András (1954-) (farmakológus, klinikai farmakológus) Nánási Péter Pál (1956-) (élettanász) Magyar János (1961-) (élettanász)
Internet cím:elektronikus változat
DOI
Borító:

3.

001-es BibID:BIBFORM003575
Első szerző:Borbély Attila (kardiológus)
Cím:Peroxynitrite-induced alpha-actinin nitration and contractile alterations in isolated human myocardial cells / Borbély A., Tóth A., Édes I., Virág L., Papp J. G., Varró A., Paulus W. J., van der Velden J., Stienen G. J. M., Papp Z.
Dátum:2005
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
myocytes
contractile function
peroxynitrite
alpha-actinin
human myocardium
Megjelenés:Cardiovascular Research. - 67 : 2 (2005), p. 225-233. -
További szerzők:Tóth Attila (1971-) (biológus) Édes István (1952-) (kardiológus) Virág László (1965-) (biokémikus, sejtbiológus, farmakológus) Papp Gy. Julius (Szeged) Varró András (1954-) (farmakológus, klinikai farmakológus) Paulus, Walter J. Velden, Jolanda, van der Stienen, Ger J. M. Papp Zoltán (1965-) (kardiológus, élettanász)
Internet cím:elektronikus változat
DOI
Borító:

4.

001-es BibID:BIBFORM020689
Első szerző:Cazorla, Olivier
Cím:Length and protein kinase A modulations of myocytes in cardiac myosin binding protein C-deficient mice / Cazorla O., Szilagyi Sz., Vignier N., Salazar, G., Kramer, E., Vassort G., Carrier L., Lacampagne A.
Dátum:2006
ISSN:0008-6363
Tárgyszavak:Orvostudományok Klinikai orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Cardiovascular Research. - 69 : 2 (2006), p. 370-380. -
További szerzők:Szilágyi Szabolcs (1976-) (kardiológus) Vignier, Nicolas Salazar, Guillermo Krämer, Elisabeth Vassort, Guy Carrier, Lucie Lacampagne, Alain
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:

5.

001-es BibID:BIBFORM018438
Első szerző:Fehér Attila (orvos)
Cím:Caveolin-1 limits the contribution of BK(Ca) channel to EDHF-mediated arteriolar dilation: implications in diet-induced obesity / Feher, A., Rutkai, I., Beleznai, T., Ungvari, Z., Csiszar, A., Edes, I., Bagi, Z.
Dátum:2010
ISSN:0008-6363
Megjegyzések:Caveolin-1 (Cav-1) interacts with large conductance Ca(2+)-activated potassium channels (BKCa) and likely exerts a negative regulatory effect on the channel activity. We investigated the role of Cav-1 in modulating BK(Ca) channel-mediated, endothelium-derived hyperpolarizing factor (EDHF)-dependent arteriolar dilation in normal condition and in an experimental model of obesity. METHODS AND RESULTS: In isolated, pressurized (80 mmHg) gracilis muscle arterioles (approximately 100 microm) of Cav-1 knockout mice, acetylcholine (ACh)-induced, EDHF-mediated dilations were enhanced and were significantly reduced by the BK(Ca) channel inhibitor, iberiotoxin (IBTX), whereas IBTX had no effect on EDHF-mediated dilations in the wild-type mice. Dilations to the selective BK(Ca) channel opener, NS-1619 were augmented in the Cav-1 knockout mice. In high-fat diet-treated, obese rats ACh-induced coronary arteriolar dilations were preserved, whereas IBTX-sensitive, ACh-induced and also NS-1619-evoked vasodilations were augmented when compared with lean animals. In coronary arterioles of obese rats a reduced protein expression of Cav-1 was detected by western immunoblotting and immunohistochemistry. Moreover, in coronary arterioles of lean rats, disruption of caveolae with methyl-beta-cyclodextrin augmented IBTX-sensitive, ACh-induced, and also NS-1619-evoked dilations. CONCLUSION: Thus, under normal conditions, Cav-1 limits the contribution of the BK(Ca) channel to EDHF-mediated arteriolar dilation. In obesity, a reduced expression of Cav-1 leads to greater contribution of the BK(Ca) channel to EDHF-mediated response, which seems essential for maintained coronary dilation.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Coronary
Microcirculation
EDHF
MaxiK channel
Caveolae
Megjelenés:Cardiovascular Research. - 87 : 4 (2010), p. 732-739. -
További szerzők:Rutkai Ibolya (1985-) (molekuláris biológus) Beleznai Tímea (1981-) (orvos) Ungvári Zoltán Csiszár Anna Édes István (1952-) (kardiológus) Bagi Zsolt (1974-) (orvos)
Pályázati támogatás:0735540T
Egyéb
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:

6.

001-es BibID:BIBFORM040577
Első szerző:Papp Zoltán (kardiológus, élettanász)
Cím:Calpain-I induced alterations in the cytoskeletal structure and impaired mechanical properties of single myocytes of rat heart / Zoltán Papp, Jolanda van der Velden, G. J. M. Stienen
Dátum:2000
ISSN:0008-6363
Megjegyzések:Objective: The involvement of Calpain-I mediated proteolysis has been implicated in myofibrillar dysfunction of reperfused myocardium following ischemia (stunning). This study addresses the question whether ultrastructural alterations might be responsible for the depressed contractility. Methods: Mechanical properties and protein composition of isolated myocytes after Calpain-I exposure (1.25 U/ml; 10 min; 15°C; pCa 5.0) and of ischemic rat hearts following reperfusion were characterized. Results: Maximal isometric force (44±5 kN/m2) at pCa 4.5 (pCa=-log[Ca2+]) decreased by 42.5% in Triton permeabilized myocytes (n=11) after Calpain-I treatment. Force (and consequent myofilament disarrangement) during Calpain-I treatment was prevented by 40 mM BDM. The contractile force of Calpain-I exposed myocytes was significantly higher at submaximal levels of activation (pCa 5.5, 5.4 and 5.3) before maximal force development (pCa 4.5) than after maximal force development. The pCa50 value (5.40±0.02) determined from these initial test contractures did not differ significantly from that of untreated controls (5.44±0.03). However, after full activation Ca2+-sensitivity of force production in Calpain-I treated myocytes was significantly reduced (pCa50 5.34±0.02). This change in pCa50 was positively correlated with the reduction in maximal isometric force and was accompanied by sarcomere disorder. These findings imply that at least part of the Calpain-I induced mechanical alterations are dependent on force history. Measurements of the rate of force redevelopment after unloaded shortening suggested that Calpain-I did not affect cross-bridge kinetics. SDS gel electrophoresis and Western immunoblotting of Calpain-I treated myocytes revealed desmin degradation. The desmin content of postischemic myocardium was also reduced. Conclusion: Our results indicate that ultrastructural alterations may play an important role in the Calpain-I mediated cardiac dysfunction.
Tárgyszavak:Orvostudományok Klinikai orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Cardiovascular Research. - 45 : 4 (2000), p. 981-993. -
További szerzők:Velden, Jolanda, van der Stienen, Ger J. M.
Pályázati támogatás:NWO-OTKA
Egyéb
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
DOI
Borító:

7.

001-es BibID:BIBFORM040584
Első szerző:Velden, Jolanda, van der
Cím:The effect of myosin light chain 2 dephosphorylation on Ca2+ -sensitivity of force is enhanced in failing human hearts / van der Velden J., Papp Z., Boontje N. M., Zaremba R., de Jong J. W., Janssen P. M., Hasenfuss G., Stienen G. J.
Dátum:2003
ISSN:0008-6363
Megjegyzések:OBJECTIVE: Phosphorylation of the myosin light chain 2 (MLC-2) isoform expressed as a percentage of total MLC-2 was decreased in failing (21.1+/-2.0%) compared to donor (31.9+/-4.8%) hearts. To assess the functional implications of this change, we compared the effects of MLC-2 dephosphorylation on force development in failing and non-failing (donor) human hearts. METHODS: Cooperative effects in isometric force and rate of force redevelopment (K(tr)) were studied in single Triton-skinned human cardiomyocytes at various [Ca(2+)] before and after protein phosphatase-1 (PP-1) incubation. RESULTS: Maximum force and K(tr) values did not differ between failing and donor hearts, but Ca(2+)-sensitivity of force (pCa(50)) was significantly higher in failing myocardium (Deltap Ca(50)=0.17). K(tr) decreased with decreasing [Ca(2+)], although this decrease was less in failing than in donor hearts. Incubation of the myocytes with PP-1 (0.5 U/ml; 60 min) decreased pCa(50) to a larger extent in failing (0.20 pCa units) than in donor cardiomyocytes (0.10 pCa units). A decrease in absolute K(tr) values was found after PP-1 in failing and donor myocytes, while the shape of the K(tr)-Ca(2+) relationships remained unaltered. CONCLUSIONS: Surprisingly, the contractile response to MLC-2 dephosphorylation is enhanced in failing hearts, despite the reduced level of basal MLC-2 phosphorylation. The enhanced response to MLC-2 dephosphorylation in failing myocytes might result from differences in basal phosphorylation of other thin and thick filament proteins between donor and failing hearts. Regulation of Ca(2+)-sensitivity via MLC-2 phosphorylation may be a potential compensatory mechanism to reverse the detrimental effects of increased Ca(2+)-sensitivity and impaired Ca(2+)-handling on diastolic function in human heart failure.
Tárgyszavak:Orvostudományok Klinikai orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Cardiovascular Research. - 57 : 2 (2003), p. 505-514. -
További szerzők:Papp Zoltán (1965-) (kardiológus, élettanász) Boontje, Nicky M. Zaremba, Ruud de Jong, J. W. Janssen, P. M. L. Hasenfuß, Gerd Stienen, Ger J. M.
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
DOI
Borító:

8.

001-es BibID:BIBFORM040582
Első szerző:Velden, Jolanda, van der
Cím:Increased Ca2+-sensitivity of the contractile apparatus in end-stage human heart failure results from altered phosphorylation of contractile proteins / van der Velden J., Papp Z., Zaremba R., Boontje N. M., de Jong J. W., Owen V. J., Burton P. B., Goldmann P., Jaquet K., Stienen G. J.
Dátum:2003
ISSN:0008-6363
Megjegyzések:OBJECTIVE: The alterations in contractile proteins underlying enhanced Ca(2+)-sensitivity of the contractile apparatus in end-stage failing human myocardium are still not resolved. In the present study an attempt was made to reveal to what extent protein alterations contribute to the increased Ca(2+)-responsiveness in human heart failure. METHODS: Isometric force and its Ca(2+)-sensitivity were studied in single left ventricular myocytes from non-failing donor (n=6) and end-stage failing (n=10) hearts. To elucidate which protein alterations contribute to the increased Ca(2+)-responsiveness isoform composition and phosphorylation status of contractile proteins were analysed by one- and two-dimensional gel electrophoresis and Western immunoblotting. RESULTS: Maximal tension did not differ between myocytes obtained from donor and failing hearts, while Ca(2+)-sensitivity of the contractile apparatus (pCa(50)) was significantly higher in failing myocardium (deltapCa(50)=0.17). Protein analysis indicated that neither re-expression of atrial light chain 1 and fetal troponin T (TnT) nor degradation of myosin light chains and troponin I (TnI) are responsible for the observed increase in Ca(2+)-responsiveness. An inverse correlation was found between pCa(50) and percentage of phosphorylated myosin light chain 2 (MLC-2), while phosphorylation of MLC-1 and TnT did not differ between donor and failing hearts. Incubation of myocytes with protein kinase A decreased Ca(2+)-sensitivity to a larger extent in failing (deltapCa(50)=0.20) than in donor (deltapCa(50)=0.03) myocytes, abolishing the difference in Ca(2+)-responsiveness. An increased percentage of dephosphorylated TnI was found in failing hearts, which significantly correlated with the enhanced Ca(2+)-responsiveness.
Tárgyszavak:Orvostudományok Klinikai orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Cardiovascular Research. - 57 : 1 (2003), p. 37-47. -
További szerzők:Papp Zoltán (1965-) (kardiológus, élettanász) Zaremba, Ruud Boontje, Nicky M. de Jong, J. W. Owen, V. J. Burton, P. B. Goldmann, P. Jaquet, Kai Stienen, Ger J. M.
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
DOI
Borító:
Rekordok letöltése1 
Corvina könyvtári katalógus v8.2.27 © 2023 Monguz kft. Minden jog fenntartva.