CCL

Összesen 7 találat.
#/oldal:
Részletezés:
Rendezés:

1.

001-es BibID:BIBFORM052173
Első szerző:Czikora Ágnes (molekuláris biológus)
Cím:Structure-activity relationships of vanilloid receptor agonists for arteriolar TRPV1 / Á. Czikora, E. Lizanecz, P. Bakó, I. Rutkai, F. Ruzsnavszky, J. Magyar, R. Pórszász, T. Kark, A. Facskó, Z. Papp, I. Édes, A. Tóth
Dátum:2012
ISSN:0007-1188
Megjegyzések:Summary Background and purpose: The vanilloid receptor 1 (TRPV1) plays a role in the activation of sensory neurons by various painful stimuli and became a therapeutic target. However, functional TRPV1 expression was also observed in the peripheral arteries affecting microvascular diameter. Experimental approach: Sensory TRPV1 activation was measured by eye wiping tests. Arteriolar TRPV1 mediated smooth muscle specific responses (arteriolar diameter, changes in intracellular Ca2+) were determined in isolated, pressurized skeletal muscle arterioles (from the rat and wild type or TRPV1-/- mice, n = 130) or in isolated canine smooth muscle cells. Vascular pharmacology of TRPV1 agonists (potency, efficacy, kinetics of action and receptor desensitization) was determined in isolated skeletal muscle arteries of the rat. Key results: Capsaicin evoked a similar constriction as norepinephrine, which was absent in TRPV knockout mice and was competitively inhibited by a TRPV1 antagonist AMG9810. Capsaicin activation resulted in an increase in intracellular Ca2+ in the arteriolar wall as well as in isolated smooth muscle cells. Other TRPV1 agonists evoked similar vascular constrictions (MSK-195, JYL-79) or were without effect (resiniferatoxin, JYL-273), although all resulted in a sensory activation (eye wiping). Maximal dose of agonists gave different kinetics of arteriolar response. A complete desensitization (tachyphylaxis) of arteriolar TRPV1 was observed (with the exception of capsaicin). Application of the partial agonist JYL-1511 suggested that about 10% TRPV1 activation is sufficient to evoke vascular tachyphylaxis without sensory activation. Conclusions and implications: Our data suggests that arteriolar TRPV1 has different structure-activity relationship compared to sensory neuron located receptor in the rat.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
vanilloid receptor (TRPV1)
resistance artery
vascular autoregulation
Megjelenés:British Journal of Pharmacology. - 165 : 6 (2012), p. 1801-1812. -
További szerzők:Lizanecz Erzsébet (1978-) (orvos) Bakó P. Rutkai Ibolya (1985-) (molekuláris biológus) Ruzsnavszky Ferenc (1984-) (élettanász) Magyar János (1961-) (élettanász) Pórszász Róbert (1965-) (farmakológus, klinikai farmakológus) Kark Tamás (1981-) (orvos) Facskó Andrea (1953-) (szemész) Papp Zoltán (1965-) (kardiológus, élettanász) Édes István (1952-) (kardiológus) Tóth Attila (1971-) (biológus)
Pályázati támogatás:TÁMOP-4.2.1/B-09/1/KONV-2010-0007
TÁMOP
Vascularis rizikó- és stroke betegek vizsgálata
K68077
OTKA
K84300
OTKA
ETT 377/2009
Egyéb
Internet cím:Szerző által megadott URL
DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:

2.

001-es BibID:BIBFORM013054
Első szerző:Harmati Gábor (élettanász)
Cím:Effects of β-adrenoceptor stimulation on delayed rectifier K(+) currents in canine ventricular cardiomyocytes / Harmati G., Bányász T., Bárándi L., Szentandrássy N., Horváth B., Szabó G., Szentmiklósi J., Szénási G., Nánási P., Magyar J.
Dátum:2011
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
isoproterenol
beta adrenerg
canine
cardiomyocyte
ionic current
Megjelenés:British Journal of Pharmacology. - 162 : 4 (2011), p. 890-896. -
További szerzők:Bányász Tamás (1960-) (élettanász) Bárándi László (1984-) (élettanász) Szentandrássy Norbert (1976-) (élettanász) Horváth Balázs (1981-) (élettanász) Szabó G. (orvos) Szentmiklósi József András (1948-) (farmakológus, klinikai laboratóriumi szakorvos) Szénási Gábor Nánási Péter Pál (1956-) (élettanász) Magyar János (1961-) (élettanász)
Internet cím:DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:

3.

001-es BibID:BIBFORM030261
035-os BibID:WOS:000184795700023
Első szerző:Kovács Anikó
Cím:Beta-adrenoceptor activation plays a role in the reverse rate-dependency of effective refractory period lengthening by dofetilide in the guinea-pig atrium, in vitro / Anikó Kovács, János Magyar, Tamás Bányász, Péter P. Nánási, Gábor Szénási
Dátum:2003
ISSN:0007-1188
Megjegyzések:1 Blockers of the rapid component of the delayed rectifier potassium current (I-Kr) prolong cardiac action potential duration (APD) and effective refractory period (ERP) in a reverse rate-dependent manner. Since activation of beta-adrenoceptors attenuates prolongation of APD evoked by I-Kr blockers, rate-dependent neuronal noradrenaline liberation in the myocardium may contribute to the reverse rate-dependent nature of the effects of I-Kr blockers. In order to test this hypothesis, we studied the effects of dofetilide, a pure I-Kr blocker, on ERP after activation or blockade of beta-adrenoceptors and after catecholamine depletion in guinea-pig left atrial myocardium paced at 3, 2 and 1 Hz, in vitro. 2 Dofetilide (100 nM) lengthened ERP in a reverse rate-dependent manner in the left atrial myocardium of guinea-pigs. Strong activation of beta-adrenoceptors using 10 nM isoproterenol abolished the dofetilide-induced lengthening of ERP at all pacing rates. 3 Blockade of the beta-adrenoceptors with metoprolol (1 muM), atenolol (3 muM) or propranolol (300 nM) increased the dofetilide-evoked prolongation of ERP at 3 and 2 Hz, but not at 1 Hz. As a consequence, metoprolol attenuated while propranolol and atenolol fully eliminated the reverse rate-dependent nature of the dofetilide-induced ERP lengthening. In catecholamine-depleted atrial preparations of the guinea-pig (24 h pretreatment with 5 mg kg(-1) reserpine i.p.), the effect of dofetilide on ERP was not frequency dependent, and propranolol did not alter the effects of dofetilide. 4 In contrast to results obtained in guinea-pig atrial preparations, propranolol failed to change the reverse rate-dependent effect of dofetilide on ERP in the right ventricular papillary muscles of rabbits and guinea-pigs. 5 As an indication of the functional consequences of rate-dependent noradrenaline liberation, propranolol decreased twitch tension at 3 and 2 Hz but not at 1 Hz in the atrial myocardium of control guinea-pigs, whereas no such effect was detected in catecholamine-depleted atrial preparations. Propranolol failed to change contractility of ventricular myocardium in guinea-pigs and rabbits. 6 It is concluded that rate-dependent noradrenaline release and the ensuing beta-adrenoceptor activation contributed to the reverse rate-dependent nature of ERP prolongation caused by I-Kr blockers in isolated guinea-pig atrial myocardium.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
egyetemen (Magyarországon) készült közlemény
Megjelenés:British Journal of Pharmacology. - 139 : 8 (2003), p. 1555-1563. -
További szerzők:Magyar János (1961-) (élettanász) Bányász Tamás (1960-) (élettanász) Nánási Péter Pál (1956-) (élettanász) Szénási Gábor
Internet cím:DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:

4.

001-es BibID:BIBFORM030259
035-os BibID:WOS:000175824200020
Első szerző:Magyar János (élettanász)
Cím:Effects of thymol on calcium and potassium currents in canine and human ventricular cardiomyocytes / János Magyar, Norbert Szentandrássy, Tamás Bányász, László Fülöp, András Varró, Péter P. Nánási
Dátum:2002
ISSN:0007-1188
Megjegyzések:1 Concentration-dependent effects of thymol (1 - 1000 pm) was Studied on action potential configuration and ionic currents in isolated canine ventricular cardiomyocytes using conventional microelectrode and patch clamp techniques. 2 Low concentration of thymol (10 muM) removed the notch of the action potential, whereas high concentrations (100 pm or higher) caused an additional shortening of action potential duration accompanied by progressive depression of plateau and reduction of V-max. 3 In the canine cells L-type Ca current (I-Ca) was decreased by thymol in a concentration-dependent manner (EC50: 158 +/- 7 muM, Hill coeff.: 2.96+/-0.43). In addition. thymol (50 - 250 muM) accelerated the inactivation of I-Ca, increased the time constant of recovery from inactivation, shifted the steady-state inactivation curve of I-Ca leftwards, but voltage dependence of activation remained unaltered. Qualitatively similar results were obtained with thymol in ventricular myocytes isolated from healthy human hearts. 4 Thymol displayed concentration-dependent suppressive effects on potassium currents: the transient outward current, I-10 (EC50: 60.6 +/- 11.4 muM, Hill coeff.: 1.03 +/- 0.11), the rapid component of the delayed rectifier, I-Kr (EC50: 63.4 +/- 6.1 muM, Hill coeff.: 1.29 +/- 0.15), and the slow component of the delayed rectifiers I-Ks (EC50: 202+/-11 muM, Hill coeff.: 0.72+/-0.14), however, K channel kinetics were not much altered by thymol. These effects on Ca and K Currents developed rapidly (within 0.5 min) and were readily reversible. 5 In conclusion, thymol suppressed cardiac ionic channels in a concentration-dependent manner, however, both drug-sensitivities as well as the mechanism of action seems to be different when blocking calcium and potassium channels.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
egyetemen (Magyarországon) készült közlemény
Megjelenés:British Journal of Pharmacology. - 136 : 2 (2002), p. 330-338. -
További szerzők:Szentandrássy Norbert (1976-) (élettanász) Bányász Tamás (1960-) (élettanász) Fülöp László (1976-) (kardiológus) Varró András (1954-) (farmakológus, klinikai farmakológus) Nánási Péter Pál (1956-) (élettanász)
Internet cím:DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:

5.

001-es BibID:BIBFORM030264
035-os BibID:WOS:000086138300017
Első szerző:Nánási Péter Pál (élettanász)
Cím:Biphasic effect of bimoclomol on calcium handling in mammalian ventricular myocardium / Péter P. Nánási, Sándor Sárközi, Gyula Szigeti, István Jóna, Csaba Szegedi, Ágnes Szabó, Tamás Bányász, János Magyar, Péter Szigligeti, Ágnes Körtvély, László Csernoch, László Kovács, Andrea Jednákovits
Dátum:2000
ISSN:0007-1188
Megjegyzések:1 Concentration-dependent effects of bimoclomol, the novel heat shock protein coinducer, on intracellular calcium transients and contractility were studied in Langendorff-perfused guinea-pig hearts loaded with the fluorescent calcium indicator dye Fura-2. Bimoclomol had a biphasic effect on contractility: both peak left ventricular pressure and the rate of force development significantly increased at a concentration of 10 nM or higher. The maximal effect was observed between 0.1 and 1 mu M, and the positive inotropic action disappeared by further increasing the concentration of bimoclomol. The drug increased systolic calcium concentration with a similar concentration-dependence. In contrast, diastolic calcium concentration increased monotonically in the presence of bimoclomol. Thus low concentrations of the drug (10-100 nM) increased, whereas high concentrations (10 mu M) decreased the amplitude of intracellular calcium transients. 2 Effects of bimoclomol on action potential configuration was studied in isolated canine ventricular myocytes. Action potential duration was increased at low (10 nM), unaffected at intermediate (0.1-1 mu M) and decreased at high (10-100 mu M) concentrations of the drug. 3 In single canine sarcoplasmic calcium release channels (ryanodine receptor), incorporated into artificial lipid bilayer, bimoclomol significantly increased the open probability of the channel in the concentration range of 1-10 mu M. The increased open probability was associated with increased mean open time. The effect of bimoclomol was again biphasic: the open probability decreased below the control level in the presence of 1 mM bimoclomol. 4 Bimoclomol (10 mu M-1 mM) had no significant effect on the rate of calcium uptake into sarcoplasmic reticulum vesicles of the dog, indicating that in vivo calcium reuptake might not substantially be affected by the drug. 5 In conclusion, the positive inotropic action of bimoclomol is likely due to the activation of the sarcoplasmic reticulum calcium release channel in mammalian ventricular myocardium.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
egyetemen (Magyarországon) készült közlemény
Megjelenés:British Journal of Pharmacology. - 129 : 7 (2000), p. 1405-1412. -
További szerzők:Sárközi Sándor (1966-) (élettanász) Szigeti Gyula (1969-) (élettanász, elektrofiziológus) Jóna István (1948-) (élettanász, fizikus) Szegedi Csaba Szabó Ágnes Bányász Tamás (1960-) (élettanász) Magyar János (1961-) (élettanász) Szigligeti Péter Körtvély Ágnes Csernoch László (1961-) (élettanász) Kovács László (1939-) (élettanász) Jednákovits Andrea
Internet cím:DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:

6.

001-es BibID:BIBFORM037321
Első szerző:Szentandrássy Norbert (élettanász)
Cím:Effects of rosiglitazone on the configuration of action potentials and ion currents in canine ventricular cells / Szentandrássy N., Harmati G., Bárándi L., Simkó J., Horváth B., Magyar J., Bányász T., Lőrincz I., Szebeni A., Kecskeméti V., Nánási P.P.
Dátum:2011
ISSN:0007-1188
Megjegyzések:BACKGROUND AND PURPOSEIn spite of its widespread clinical application, there is little information on the cellular cardiac effects of the antidiabetic drug rosiglitazone in larger experimental animals. In the present study therefore concentration-dependent effects of rosiglitazone on action potential morphology and the underlying ion currents were studied in dog hearts.EXPERIMENTAL APPROACHStandard microelectrode techniques, conventional whole cell patch clamp and action potential voltage clamp techniques were applied in enzymatically dispersed ventricular cells from dog hearts.KEY RESULTSAt concentrations ?10 mM rosiglitazone decreased the amplitude of phase-1 repolarization, reduced the maximum velocity of depolarization and caused depression of the plateau potential. These effects developed rapidly and were readily reversible upon washout. Rosiglitazone suppressed several transmembrane ion currents, oncentration-dependently, under conventional voltageclamp conditions and altered their kinetic properties. The EC50 value for this inhibition was 25.2 ? 2.7 mM for the transient outward K+ current (Ito), 72.3 ? 9.3 mM for the rapid delayed rectifier K+ current (IKr) and 82.5 ? 9.4 mM for the L-type Ca2+ current (ICa) with Hill coefficients close to unity. The inward rectifier K+ current (IK1) was not affected by rosiglitazone up to concentrations of 100 mM. Suppression of Ito, IKr, and ICa was confirmed also under action potential voltage clamp conditions.CONCLUSIONS AND IMPLICATIONSAlterations in the densities and kinetic properties of ion currents may carry serious pro-arrhythmic risk in case of overdose with rosiglitazone, especially in patients having multiple cardiovascular risk factors, like elderly diabetic patients.
Tárgyszavak:Orvostudományok Egészségtudományok idegen nyelvű folyóiratközlemény külföldi lapban
antidiabetic agents
rosiglitazone
dog cardiomyocytes
action potential
ion currents
Megjelenés:British Journal Of Pharmacology 163 : 3 (2011), p. 499-509. -
További szerzők:Harmati Gábor (1983-) (élettanász) Bárándi László (1984-) (élettanász) Simkó József (1974-) (belgyógyász, kardiológus) Horváth Balázs (1981-) (élettanász) Magyar János (1961-) (élettanász) Bányász Tamás (1960-) (élettanász) Lőrincz István (1950-) (belgyógyász, kardiológus) Szebeni Andrea Kecskeméti Valéria Nánási Péter Pál (1956-) (élettanász)
Pályázati támogatás:TÁMOP-4.2.1/B-09/1/KONV-2010-0007
TÁMOP
A feszültségfüggő K-csatornák szerepe excitábilis sejtekben
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
DOI
Szerző által megadott URL
Borító:

7.

001-es BibID:BIBFORM037346
Első szerző:Szentandrássy Norbert (élettanász)
Cím:Role of action potential configuration and the contribution of Ca2+ and K+ currents to isoprenaline-induced changes in canine ventricular cells / N. Szentandrássy, V. Farkas, L. Bárándi, B. Hegyi, F. Ruzsnavszky, B. Horváth, T. Bányász, J. Magyar, I. Márton, P. P. Nánási
Dátum:2012
ISSN:0007-1188
Megjegyzések:BACKGROUND AND PURPOSE: Although isoprenaline (ISO) is known to activate several ion currents in mammalian myocardium, little is known about the role of action potential morphology in the ISO-induced changes in ion currents. Therefore, the effects of ISO on action potential configuration, L-type Ca2+ current (ICa), slow delayed rectifier K+ current (IKs) and fast delayed rectifier K+ current (IKr)were studied and compared in a frequency-dependent manner using canine isolated ventricular myocytes from varioustransmural locations.EXPERIMENTAL APPROACHAction potentials were recorded with conventional sharp microelectrodes; ion currents were measured using conventional and action potential voltage clamp techniques.KEY RESULTSIn myocytes displaying a spike-and-dome action potential configuration (epicardial and midmyocardial cells), ISO caused reversible shortening of action potentials accompanied by elevation of the plateau. ISO-induced action potential shortening was absent in endocardial cells and in myocytes pretreated with 4-aminopyridine. Application of the IKr blocker E-4031 failed to modify the ISO effect, while action potentials were lengthened by ISO in the presence of the IKs blocker HMR-1556. Bothaction potential shortening and elevation of the plateau were prevented by pretreatment with the ICa blocker nisoldipine.Action potential voltage clamp experiments revealed a prominent slowly inactivating ICa followed by a rise in IKs, both currents increased with increasing the cycle length.CONCLUSIONS AND IMPLICATIONSThe effect of ISO in canine ventricular cells depends critically on action potential configuration, and the ISO-induced activation of IKs ? but not IKr ? may be responsible for the observed shortening of action potentials
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
heart
action potential
calcium current
potassium current
Megjelenés:British Journal of Pharmacology. - 167 : 3 (2012), p. 599-611. -
További szerzők:Farkas Viktória Bárándi László (1984-) (élettanász) Hegyi Bence (1987-) (élettanász) Ruzsnavszky Ferenc (1984-) (élettanász) Horváth Balázs (1981-) (élettanász) Bányász Tamás (1960-) (élettanász) Magyar János (1961-) (élettanász) Márton Ildikó (1954-) (fogszakorvos) Nánási Péter Pál (1956-) (élettanász)
Pályázati támogatás:TÁMOP-4.2.1/B-09/1/KONV-2010-0007
TÁMOP
A feszültségfüggő K-csatornák szerepe excitábilis sejtekben
Internet cím:DOI
Intézményi repozitóriumban (DEA) tárolt változat
Borító:
Rekordok letöltése1 
Corvina könyvtári katalógus v8.2.27 © 2023 Monguz kft. Minden jog fenntartva.