Purpose: Previous studies have examined the effects of c-irradiation (c-IR) on wild-type and p53
mutant Medaka (Oryzias latipes) 24 hours after irradiation and in the present work, apoptosis and alterations
in erythrocytes of 4, 8 and 24 h and 14 days after gamma-ray irradiation were reported as genotoxic
biomarkers of c-irradiation.
Materials and methods: Sexually mature wild-type, WT (Hd-rR) and p53(
/
) adult female medaka
(O. latipes) were exposed to 4 Gy dose of c-IR and sampling were collected after 4, 8 and 24 h and
14 days.
Results: Apoptosis and morphological alterations were observed from 4 h after irradiation and remarkably
increased 8 h after irradiation in the wild-type. Apoptotic cell death has been observed 8 h after
irradiation most prominently but subtle in p53 mutant medaka. All these phenotypes were recovered
14 days after irradiation in both strains. Although no micronuclei were seen in any group, nuclear
abnormalities were observed in red blood cells. Both apoptosis and morphological alterations in erythrocytes
were decreased after 24 and 14 days after c-irradiation.
Conclusions: We conclude that apoptosis and malformations caused by 4 Gy c-irradiation in the erythrocytes
of medaka fish occurs from 4–24 h and the initial response until 8 h was p53-dependent.