Some properties of the signals involved in unirradiated zebrafish embryos rescuing α-particle irradiated zebrafish embryos

AbstractPurpose: The in vivo radiation-induced bystander effect (RIBE) and radiation-induced rescue effect (RIRE) induced between embryos of the zebrafish (Danio rerio) by alpha-particle irradiation were studied through the number of apoptotic signals revealed at 24 h post fertilization (hpf) through vital dye acridine orange staining.Materials and methods: RIBE and RIRE were verified through the significant increase and decrease in apoptotic signals in the partnered bystander and irradiated embryos, respectively.Results: The medium transfer experiment where irradiated zebrafish embryos were rescued through immersion in the medium previously conditioned by a larger number of irradiated zebrafish embryos showed (a) the involvement of a released stress signal in the induction of RIRE, and (b) RIBE and RIRE signals had the same function. With the help of 500 μM of the specific nitric oxide (NO) scavenger cPTIO (2-(4carboxyphenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide), NO was confirmed as an essenti...