Transient Elevation of Glucose Increases Arrhythmia Susceptibility in Non-Diabetic Rat Trabeculae With Non-Uniform Contraction.
Circ J
; 84(4): 551-558, 2020 03 25.
Article
em En
| MEDLINE
| ID: mdl-32092718
ABSTRACT
BACKGROUND:
In non-diabetic patients with acute coronary syndrome, stress hyperglycemia occasionally occurs and is related to their mortality. Whether transient elevation of glucose affects arrhythmia susceptibility in non-diabetic hearts with non-uniform contraction was examined.MethodsâandâResults:
Force, intracellular Ca2+([Ca2+]i), and membrane potential were measured in trabeculae from rat hearts. Non-uniform contraction was produced by a jet of paralyzing solution. Ca2+waves and arrhythmias were induced by electrical stimulation (2.0 mmol/L [Ca2+]o). The activity of Ca2+/calmodulin-dependent protein kinaseII (CaMKII) was measured. An elevation of glucose from 150 to 400 mg/dL increased the velocity of Ca2+waves and the number of spontaneous action potentials triggered by electrical stimulation. Besides, the elevation of glucose increased the CaMKII activity. In the presence of 1 µmol/L KN-93, the elevation of glucose did not increase the velocity of Ca2+waves and the number of triggered action potentials. In addition, in the presence of 1 µmol/L autocamtide-2 related inhibitory peptide or 50 µmol/L diazo-5-oxonorleucine, the elevation of glucose did not increase the number of triggered action potentials. Furthermore, the elevation of glucose by adding L-glucose did not increase their number.CONCLUSIONS:
In non-diabetic hearts with non-uniform contraction, transient elevation of glucose increases the velocity of Ca2+waves by activating CaMKII,probably through glycosylation with O-linked ß-N-acetylglucosamine, thereby increasing arrhythmia susceptibility.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Arritmias Cardíacas
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Função Ventricular Direita
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Miócitos Cardíacos
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Glucose
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Frequência Cardíaca
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Ventrículos do Coração
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Contração Miocárdica
Limite:
Animals
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article