Abstract
Background To obtain therapeutic condition precisely by in vitro experiment, we studied the irradiance dependence of the electrical conduction blockage caused by a photodynamic reaction using a high extracellular concentration of talaporfin sodium on a novel in vitro cardiomyocyte electrical conduction wire. Methods The cardiomyocyte wires were constructed on patterned cultivation cover glass, which had cultivation areas 60 μm in width, and a maximum length of 10 mm. The talaporfin sodium concentration was set to 20 μg/mL. The photodynamic reaction with a high extracellular photosensitizer concentration was performed with a short time interval (approximately 15 min) between photosensitizer exposure and irradiation. A 663-nm laser was applied to the cardiomyocyte wire, and the irradiance was varied between 3 and 120 mW/cm2. The cardiomyocyte electrical conduction was evaluated using the cross-correlation function of intracellular Ca2+ probe fluorescence brightness from an upper and lower section outside the laser irradiation area of a wire every 10 s, which lasted up to 600 s. Results The onset of electrical conduction blockage was defined by an 85% decrease in the cross-correlation function, compared with its initial value. The time for the electrical conduction blockage decreased from 600 to 300 s as the irradiance was increased. Also, the probability of electrical conduction blockage was found to increase with increasing irradiance. Conclusions We found a strong dependence on the irradiance for the time and probability of electrical conduction blockage.
| Original language | English |
|---|---|
| Pages (from-to) | 93-97 |
| Number of pages | 5 |
| Journal | Photodiagnosis and Photodynamic Therapy |
| Volume | 19 |
| DOIs | |
| Publication status | Published - 2017 Sep 1 |
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Keywords
- Cross-correlation function
- Electrical conduction
- Interstitial fluid
- Myocardial cell
- Photodynamic reaction
- Talaporfin sodium
ASJC Scopus subject areas
- Biophysics
- Oncology
- Dermatology
- Pharmacology (medical)
Cite this
Irradiance dependence of the conduction block of an in vitro cardiomyocyte wire. / Ogawa, Emiyu; Kurotsu, Mariko; Arai, Tsunenori.
In: Photodiagnosis and Photodynamic Therapy, Vol. 19, 01.09.2017, p. 93-97.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Irradiance dependence of the conduction block of an in vitro cardiomyocyte wire
AU - Ogawa, Emiyu
AU - Kurotsu, Mariko
AU - Arai, Tsunenori
PY - 2017/9/1
Y1 - 2017/9/1
N2 - Background To obtain therapeutic condition precisely by in vitro experiment, we studied the irradiance dependence of the electrical conduction blockage caused by a photodynamic reaction using a high extracellular concentration of talaporfin sodium on a novel in vitro cardiomyocyte electrical conduction wire. Methods The cardiomyocyte wires were constructed on patterned cultivation cover glass, which had cultivation areas 60 μm in width, and a maximum length of 10 mm. The talaporfin sodium concentration was set to 20 μg/mL. The photodynamic reaction with a high extracellular photosensitizer concentration was performed with a short time interval (approximately 15 min) between photosensitizer exposure and irradiation. A 663-nm laser was applied to the cardiomyocyte wire, and the irradiance was varied between 3 and 120 mW/cm2. The cardiomyocyte electrical conduction was evaluated using the cross-correlation function of intracellular Ca2+ probe fluorescence brightness from an upper and lower section outside the laser irradiation area of a wire every 10 s, which lasted up to 600 s. Results The onset of electrical conduction blockage was defined by an 85% decrease in the cross-correlation function, compared with its initial value. The time for the electrical conduction blockage decreased from 600 to 300 s as the irradiance was increased. Also, the probability of electrical conduction blockage was found to increase with increasing irradiance. Conclusions We found a strong dependence on the irradiance for the time and probability of electrical conduction blockage.
AB - Background To obtain therapeutic condition precisely by in vitro experiment, we studied the irradiance dependence of the electrical conduction blockage caused by a photodynamic reaction using a high extracellular concentration of talaporfin sodium on a novel in vitro cardiomyocyte electrical conduction wire. Methods The cardiomyocyte wires were constructed on patterned cultivation cover glass, which had cultivation areas 60 μm in width, and a maximum length of 10 mm. The talaporfin sodium concentration was set to 20 μg/mL. The photodynamic reaction with a high extracellular photosensitizer concentration was performed with a short time interval (approximately 15 min) between photosensitizer exposure and irradiation. A 663-nm laser was applied to the cardiomyocyte wire, and the irradiance was varied between 3 and 120 mW/cm2. The cardiomyocyte electrical conduction was evaluated using the cross-correlation function of intracellular Ca2+ probe fluorescence brightness from an upper and lower section outside the laser irradiation area of a wire every 10 s, which lasted up to 600 s. Results The onset of electrical conduction blockage was defined by an 85% decrease in the cross-correlation function, compared with its initial value. The time for the electrical conduction blockage decreased from 600 to 300 s as the irradiance was increased. Also, the probability of electrical conduction blockage was found to increase with increasing irradiance. Conclusions We found a strong dependence on the irradiance for the time and probability of electrical conduction blockage.
KW - Cross-correlation function
KW - Electrical conduction
KW - Interstitial fluid
KW - Myocardial cell
KW - Photodynamic reaction
KW - Talaporfin sodium
UR - http://www.scopus.com/inward/record.url?scp=85020257743&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85020257743&partnerID=8YFLogxK
U2 - 10.1016/j.pdpdt.2017.05.008
DO - 10.1016/j.pdpdt.2017.05.008
M3 - Article
C2 - 28502877
AN - SCOPUS:85020257743
VL - 19
SP - 93
EP - 97
JO - Photodiagnosis and Photodynamic Therapy
JF - Photodiagnosis and Photodynamic Therapy
SN - 1572-1000
ER -