Hostname: page-component-78c5997874-g7gxr Total loading time: 0 Render date: 2024-11-19T04:24:51.416Z Has data issue: false hasContentIssue false
  • English
  • Français

Bystander effects in bullfrog tadpoles

Published online by Cambridge University Press:  09 January 2012

J. Barescut ,
D. Lariviere ,
T. Stocki ,
M. Audette-Stuart  and
T. Yankovich
M. Audette-Stuart*
Affiliation:
Environmental Technologies Branch, Atomic Energy of Canada Limited (AECL), Chalk River, Ontario, K0J 1J0, Canada
T. Yankovich
Affiliation:
Environmental Technologies Branch, Atomic Energy of Canada Limited (AECL), Chalk River, Ontario, K0J 1J0, Canada
*
e-mail: [email protected]
Get access

Abstract

Adaptive responses were observed using the micronucleus frequency in bullfrog tadpoles. In tanks in which control tadpoles were placed in contact with tadpoles that were previously housed in tritiated water (3.0 × 104 Bq/L), the cells from all animals responded as though they were “adapted”. This suggests that direct exposure to 3.0 × 104 Bq/L tritium contributes to an increased resistance to a high dose of radiation in liver cells. It also suggests that being in contact with tadpoles that were previously exposed to 3.0 × 104 Bq/L tritium (bystander effect) contributes to an increased resistance to a high dose of radiation in liver cells.

In vitro exposures were also conducted using primary cultures of liver cells obtained from an unexposed-non-bystander tadpole. In these control cells, it was observed that exposure to 100 mGy of 60Co gamma radiation (delivered at a dose rate of 5 mGy/min) did not affect the micronucleus frequency whereas exposure to 4 Gy (delivered at a dose rate of about 10.2 Gy/min) increased the micronucleus frequency. Prior exposure to a low dose of 60Co gamma radiation (100 mGy delivered at a dose rate of 5 mGy/min) induced an adaptive response, protecting the cells from harm caused by exposure to subsequent high doses of 60Co gamma radiation (4 Gy delivered at a dose rate of about 10.2 Gy/min). Using the adaptive response (determined using micronucleus assay) as a biomarker, the data obtained suggest that bystander effects do play a role in wild populations since bullfrog tadpoles that were not exposed to tritium responded like the tadpoles that were directly exposed to tritium after being placed in contact with them.

Type
Research Article
Information
Radioprotection , Volume 46 , Issue 6: ICRER 2011 – International Conference on Radioecology & Environmental Radioactivity: Environment & Nuclear Renaissance , 2011 , pp. S497
Copyright
© Owned by the authors, published by EDP Sciences, 2011

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Boreham, D.R., A. Trivedi and R.E.J. Mitchel. 1991. Radiation and stress response in Saccharomyces cerevisiae. In Prasad, R., Yeast Molecular Biology and Biotechnology (pp. 294-314). New Delhi, India: Omega Scientific Publishers.
Cai, L. and M.G. Cherian. 1996. Adaptive response to ionizing radiation-induced chromosome aberrations in rabbit lymphocytes: effect of pre-exposure to zinc, and copper salts. Mutat. Res., 369: 233-241.
Flores, M.J., J. Pinero, T. Ortiz, N. Pastor, J.C. Mateos and F. Cortes. 1996. Both bovine and rabbit lymphocytes conditioned with hydrogen peroxide show an adaptive response to radiation damage. Mutat. Res., 372: 9-15.
Mitchel, R.E., N.J. Gragtmans and D.P. Morrison. 1990. Beta-radiation-induced resistance to MNNG initiation of papilloma but not carcinoma formation in mouse skin. Radiat. Res., 121: 180-186.
Boreham, D.R., J.A. Dolling, S.R. Maves, S. Miller, D.P. Morrison and R.E. Mitchel. 1997. Heat-induced thermal tolerance and radiation resistance to apoptosis in human lymphocytes. Biochem. Cell Biol., 75: 393-397.
Cregan, S.P., D.R. Boreham, P.R. Walker, D.L. Brown and R.E. Mitchel. 1994. Modification of radiation-induced apoptosis in radiation- or hyperthermia-adapted human lymphocytes. Biochem. Cell Biol., 72: 475-482.
Ryan, L.A., C.B. Seymour, A. O’Neill-Mehlenbacher and C.E. Mothersill. 2008. Radiation-induced adaptive response in fish cell lines. J. Env. Radioactivity, 99: 739-747.
Culley, D.D. (1992). Managing a Bullfrog Research Colony in “The Care and Use of Amphibians, Reptiles and Fish in Research”, Proceedings from a Scientists Centre for Animal Welfare (SCAW)/ Louisiana State University School of Veterinary Medicine (LSUSVM)-sponsored conference held April 8-9, 1991 in New Orleans, Louisiana with additional material provided by the authors (Published in November 1992), pp.30-39.
Fenech, M., W.P. Chang, M. Kirsch-Volders, N. Holland, S. Bonassi and E. Zeiger. 2003. HUMN project: detailed description of the scoring criteria for the cytokinesis-block micronucleus assay using isolated human lymphocyte cultures. Mutat. Res. 534: 65-75.