title: Look Different: Effect of Radiation Hormesis on the Survival Rate of Immunosuppressed Mice.
abstract: BACKGROUND
  Hormesis is defined as the bio-positive response of something which is bio-negative in high doses. In the present study, the effect of radiation hormesis was evaluated on the survival rate of immunosuppressed BALB/c mice by Cyclosporine A.
  
  
  METHODS
  We used 75 consanguine, male, BALB/c mice in this experiment. The first group received Technetium-99m and the second group was placed on a sample radioactive soil of Ramsar region (800Bq) for 20 days. The third group was exposed to X-rays and the fourth group was placed on the radioactive soil and then injected Technetium-99m. The last group was the sham irradiated control group. Finally, 30mg Cyclosporine A as the immunosuppressive agent was orally administered to all mice 48 hours after receiving X-rays and Technetium-99m. The mean survival rate of mice in each group was estimated during time.
  
  
  RESULTS
  A log rank test was run to determine if there were differences in the survival distribution for different groups and related treatments. According to the results, the survival rate of all pre-irradiated groups was more than the sham irradiated control group (p < .05). The highest survival time was related to the mice which were placed on the radioactive soil of Ramsar region for 20 days and then injected Technetium-99m.
  
  
  CONCLUSIONS
  This study confirmed the presence of hormetic models and the enhancement of survival rate in immunosuppressed BALB/c mice as a consequence of low-dose irradiation. It is also revealed the positive synergetic radioadaptive response on survival rate of immunosuppressed animals.
authors.affiliation: Ionizing and Non-Ionizing Radiation Protection Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: M
authors.initials: M
authors.lastname: Alavi
authors.affiliation: Ionizing and Non-Ionizing Radiation Protection Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: S
authors.initials: S
authors.lastname: Taeb
authors.affiliation: Diagnostic Laboratory Sciences and Technology Research Center, School of Paramedical Sciences, Shiraz University of Medical sciences, Shiraz, Iran.
authors.forename: M A
authors.initials: MA
authors.lastname: Okhovat
authors.affiliation: Ionizing and Non-Ionizing Radiation Protection Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran ; Master Student of Biophysics, Payame Noor University (PNU), Iran.
authors.forename: M
authors.initials: M
authors.lastname: Atefi
authors.affiliation: Department Of Mathematics, Neyriz Branch, Islamic Azad University, Neyriz, Iran.
authors.forename: F
authors.initials: F
authors.lastname: Negahdari
keywords:  BALB/c mice ;  Cyclosporine A ;  Radioadaptive Response;  Survival Rate ; Radiation Hormesis 