RRC ID 1934
著者 Kawauchi S, Sato S, Morimoto Y, Kikuchi M.
タイトル Correlation between oxygen consumption and photobleaching during in vitro photodynamic treatment with ATX-S10.Na(II) using pulsed light excitation: dependence of pulse repetition rate and irradiation time.
ジャーナル Photochem Photobiol
Abstract We revealed that in ATX-S10.Na(II)(13,17-bis (1-carboxypropionyl) carbamoylethyl-8-etheny-2-hydroxy-3-hydroxyiminoethylidene-2,7,12,18-tetraethyl porphyrin sodium)-mediated photodynamic therapy using 667 nm nanosecond-pulsed light excitation at a peak intensity of 2.0 MW/cm(2), phototoxicity increased with decreasing pulse repetition rate in the range of 5-30 Hz for A549 cell cultures. To examine the relation between the reaction mechanism and measured phototoxicity, we carefully measured the kinetics of photochemical oxygen consumption and photobleaching during irradiation of ATX-S10.Na(II)-sensitized A549 monolayer cultures. Measurements of oxygen consumption with a microelectrode, which was performed just above the cells, showed that there was no significant difference between the magnitudes of decrease in oxygen at the three repetition rates at the same cumulative fluence. Loss of ATX-S10.Na(II) fluorescence intensity also exhibited little repetition rate dependence when compared at the same cumulative fluence. We investigated the correlation between oxygen consumption and photobleaching during irradiation and obtained "fluorescence-oxygen diagrams." The diagrams showed dynamic changes between oxygen-dependent and oxygen-independent photobleaching at the higher repetition rates of 10 and 30 Hz, whereas such change was not clearly seen over the whole irradiation time at 5 Hz. These results suggest that the reduced phototoxicity at high repetition rates might be due to an oxygen-independent reaction. We presumed that the change in the reaction mechanism was associated with the local concentrations of the photosensitizer and oxygen in cells during irradiation.
巻・号 80(2)
ページ 216-23
公開日 2004-1-1
DOI 10.1562/2004-03-27-RA-125
PII 2004-03-27-RA-125
PMID 15244505
MeSH Cell Line, Tumor Cell Survival / drug effects Cell Survival / radiation effects Humans Light* Oxygen Consumption / drug effects* Oxygen Consumption / radiation effects* Photobleaching / drug effects* Photobleaching / radiation effects* Porphyrins / chemistry Porphyrins / pharmacology* Spectrometry, Fluorescence Time Factors
IF 2.721
引用数 15
WOS 分野 BIOPHYSICS BIOCHEMISTRY & MOLECULAR BIOLOGY
リソース情報
ヒト・動物細胞 A549(RCB0098)