PMID- 18654045
OWN - NLM
STAT- MEDLINE
DCOM- 20081125
LR  - 20190513
IS  - 0449-3060 (Print)
IS  - 0449-3060 (Linking)
VI  - 49
IP  - 5
DP  - 2008 Sep
TI  - Rapid and simple method for quantitative evaluation of neurocytotoxic effects of 
      radiation on developing medaka brain.
PG  - 533-40
AB  - We describe a novel method for rapid and quantitative evaluation of the degree of 
      radiation-induced apoptosis in the developing brain of medaka (Oryzias latipes). 
      Embryos at stage 28 were irradiated with 1, 2, 3.5, and 5 Gy x-ray. Living 
      embryos were stained with a vital dye, acridine orange (AO), for 1-2 h, and 
      whole-mount brains were examined under an epifluorescence microscope. From 7 to 
      10 h after irradiation with 5 Gy x-ray, we found two morphologically different 
      types of AO-stained structures, namely, small single nuclei and rosette-shaped 
      nuclear clusters. Electron microscopy revealed that these two distinct types of 
      structures were single apoptotic cells with condensed nuclei and aggregates of 
      apoptotic cells, respectively. From 10 to 30 h after irradiation, a similar 
      AO-staining pattern was observed. The numbers of AO-stained rosette-shaped 
      nuclear clusters and AO-stained single nuclei increased in a dose-dependent 
      manner in the optic tectum. We used the number of AO-stained rosette-shaped 
      nuclear clusters/optic tectum as an index of the degree of radiation-induced 
      brain cell death at 20-24 h after irradiation. The results showed that the number 
      of rosette-shaped nuclear clusters/optic tectum in irradiated embryos exposed to 
      2 Gy or higher doses was highly significant compared to the number in 
      nonirradiated control embryos, whereas no difference was detected at 1 Gy. Thus, 
      the threshold dose for brain cell death in medaka embryos was taken as being 
      between 1-2 Gy, which may not be so extraordinarily large compared to those for 
      rodents and humans. The results show that medaka embryos are useful for 
      quantitative evaluation of developmental neurocytotoxic effects of radiation.
FAU - Yasuda, Takako
AU  - Yasuda T
AD  - Environmental Radiation Effects Research Group, Research Center for Radiation 
      Protection, National Institute of Radiological Sciences, Chiba, Japan. 
      t_yasuda@nirs.go.jp
FAU - Yoshimoto, Masami
AU  - Yoshimoto M
FAU - Maeda, Keiko
AU  - Maeda K
FAU - Matsumoto, Atsuko
AU  - Matsumoto A
FAU - Maruyama, Kouichi
AU  - Maruyama K
FAU - Ishikawa, Yuji
AU  - Ishikawa Y
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20080724
PL  - England
TA  - J Radiat Res
JT  - Journal of radiation research
JID - 0376611
SB  - IM
MH  - Animals
MH  - Apoptosis/*radiation effects
MH  - Brain/*cytology/embryology/*radiation effects
MH  - Dose-Response Relationship, Radiation
MH  - Embryo, Nonmammalian/cytology/radiation effects
MH  - Neurons/*cytology/*radiation effects
MH  - Oryzias/*embryology/*physiology
MH  - Radiation Dosage
EDAT- 2008/07/26 09:00
MHDA- 2008/12/17 09:00
CRDT- 2008/07/26 09:00
PHST- 2008/07/26 09:00 [pubmed]
PHST- 2008/12/17 09:00 [medline]
PHST- 2008/07/26 09:00 [entrez]
AID - JST.JSTAGE/jrr/08030 [pii]
AID - 10.1269/jrr.08030 [doi]
PST - ppublish
SO  - J Radiat Res. 2008 Sep;49(5):533-40. doi: 10.1269/jrr.08030. Epub 2008 Jul 24.