@article{oai:repo.qst.go.jp:00045679,
 author = {Yasuda, Takako and Oda, Shoji and Ishikawa, Yuuji and Asaka, Tomomi and Hidaka, Masayuki and Yasuda, Hiroshi and Anzai, Kazunori and Mitani, Hiroshi and 石川 裕二 and 保田 浩志 and 安西 和紀},
 issue = {6},
 journal = {Journal of Radiation Research},
 month = {Nov},
 note = {For sequential observation of radiation-induced apoptosis in a living embryo, we injected Acridine Orange (AO) solution into the yolk of embryo and visualized radiation-induced apoptosis in developing optic tectum (OT). Medaka embryos at stage 28, when neural cells proliferate rapidly in the OT, were irradiated with 5 Gy X-rays which is non-lethal dose for irradiated embryos at hatching. The irradiated embryos hatched normally without morphological abnormalities in their brains, even though a large number of apoptotic cells were induced transiently in OT. By yolk injection, apoptotic cells in OT were distinguished as AO-positive small nuclei at 3 h after irradiation. At 8-10 h after irradiation, AO-positive rosette-shaped clusters were obviously distinguished in marginal tectal regions of OT where cells are proliferating intensely. The AO-positive clusters became bigger and more obvious, but its number did not increase up to 24 h after irradiation and completely disappeared up to 49 h after irradiation. This characteristic appearance of the AO-positive nuclei/clusters is in a good agreement with our previous results based on the examination of fixed specimens stained with AO by injection into the peri-vitelline space, suggesting that the AO-yolk injection method is highly reliable for detecting apoptotic cells in living embryos. The live imaging of apoptotic cells in developing Medaka embryos by AO-yolk injection method is expected to reveal more in details of dynamics of the apoptotic responses in the irradiated brain and other tissues.},
 pages = {487--494},
 title = {Live Imaging of Radiation-Induced Apoptosis by Yolk Injection of Acridine Orange in the Developing Optic Tectum of Medaka},
 volume = {50},
 year = {2009}
}