High-precision recording of the action potential in isolated cardiomyocytes using the near-infrared fluorescent dye di-4-ANBDQBS.
Am J Physiol Heart Circ Physiol
; 299(4): H1271-81, 2010 Oct.
Article
em En
| MEDLINE
| ID: mdl-20601458
ABSTRACT
The use of voltage-sensitive fluorescent dyes (VSD) for noninvasive measurement of the action potential (AP) in isolated cells has been hindered by low-photon yield of the preparation, dye toxicity, and photodynamic damage. Here we used a new red-shifted VSD, di-4-ANBDQBS, and a fast electron-multiplied charge-coupled device camera for optical AP (OAP) recording in guinea pig cardiac myocytes. Loading di-4-ANBDQBS did not alter APs recorded with micropipette. With short laser exposures (just enough to record one OAP every 1-5 min), di-4-ANBDQBS yielded fluorescent signals with very high signal-to-background ratios (change in fluorescence on depolarization/fluorescence at resting potential 19.2 ± 4.1%) and signal-to-noise ratios (40 ± 13.2). Quantum chemical calculations comparing the ANBDQ chromophore to the conventional ANEP chromophore showed that the higher wavelength and the greater voltage sensitivity of the former have the same electro-optical origin a longer path for electron redistribution in the excited state. OAP closely tracked simultaneously recorded electrical APs, permitting measurement of AP duration within 1% error. Prolonged laser exposure caused progressive AP duration prolongation and instability. However, these effects were alleviated or abolished by reducing the dye concentration and by perfusion with antioxidants. Thus the presented technique provides a unique opportunity for noninvasive AP recording in single cardiomyocytes.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Compostos de Quinolínio
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Potenciais de Ação
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Técnicas de Patch-Clamp
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Miócitos Cardíacos
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Corantes Fluorescentes
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2-Naftilamina
Limite:
Animals
Idioma:
En
Revista:
Am J Physiol Heart Circ Physiol
Assunto da revista:
CARDIOLOGIA
/
FISIOLOGIA
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Estados Unidos