Effects of tumor necrosis factor alpha on expression of phospholamban and intracellular calcium in cardiomyocytes / 中国医学科学院学报
Acta Academiae Medicinae Sinicae
; (6): 767-771, 2005.
Article
de Zh
| WPRIM
| ID: wpr-318819
Bibliothèque responsable:
WPRO
ABSTRACT
<p><b>OBJECTIVE</b>To explore the effects of tumor necrosis factor alpha (TNFalpha) on the expression of phospholamban (PLB) and sarco (endo) plasmic reticulum Ca(2+)-ATPase (SERCA2a) and concentration of intracellular free calcium in myocardiocytes.</p><p><b>METHODS</b>The neonatal rat myocardiocytes were randomly divided into 6 groups: treatment with different concentrations of TNFalpha (1,10,30,50,and 70 microg/L, respectively) and without TNFalpha (control). The mRNA and protein expression of PLB and SERCA2a were detected with one-step reverse transcription-polymerase chain reaction and Western blotting. The changes of intracellular free calcium concentration ([Ca2+]i) in cultured single neonatal rat cardiomyocyte were determined with Fluo-3/AM loading by laser scanning confocal microscopy. RESULTS TNFalpha significantly increased the expression of PLB mRNA and protein in a dose-dependent fashion. The ratio of PLB/beta-actin mRNA in myocardiocytes incubated with 10,30,50, and 70 microg/L TNFalpha significantly increased by 66%, 106%, 141%, and 189% compared with control (P < 0.05), and protein levels significantly increased by 30%, 48%, 73%, and 114% respectively compared with control (P < 0.001), but there was no significant difference in PLB mRNA expression between the group treated with 1 microg/L TNFalpha and control group. TNFalpha had no effect on the expression of mRNA and protein of SERCA2a. TNFalpha (50 microg/L) incubated with cell for 24 hours diminished delta[Ca2+]i of single neonatal rat cardiomyocyte about 33% stimulated by isoproterenol (P < 0.01), but had no effect on delta [Ca2+]i of cardiomyocyte without isoproterenol stimulation.</p><p><b>CONCLUSION</b>TNFalpha can increase the expression of PLB and decrease delta[Ca2+]i in cardiomyocytes, which may be related with its negative inotropic effects on cardiomyocytes.</p>
Texte intégral:
1
Indice:
WPRIM
Sujet Principal:
Pharmacologie
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Protéines de liaison au calcium
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ARN messager
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Cellules cultivées
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Calcium
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Facteur de nécrose tumorale alpha
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Rat Wistar
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Myocytes cardiaques
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Sarcoplasmic Reticulum Calcium-Transporting ATPases
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Génétique
Limites du sujet:
Animals
langue:
Zh
Texte intégral:
Acta Academiae Medicinae Sinicae
Année:
2005
Type:
Article