Cell death by apoptosis in the neonatal mouse cerebellum following gamma-irradiation.
We have studied, by a nonisotopic in situ DNA end-labeling (ISEL) technique, the frequency of apoptosis in the external granular layer (EGL) of the cerebellum after whole-body irradiation of newborn mice by gamma-rays from 60Co. The total number of normal cells and cells showing morphological features of apoptosis were counted. The frequency of apoptotic cells was expressed as a percentage of the total number of cells in EGL. The extent of changes following 2 Gy (10.9 Gy/min) was studied at 2, 4, 6, 8, 12, or 24 hours after exposure. The maximal frequency was found 6-8 hours after exposure. Newborn mice that received 0.18, 0.36, 0.54, 1.08, 1.98, or 3.96 Gy were examined 6 hours after irradiation. Measurements performed after irradiation showed a dose-related increase in apoptotic cells in each of the mice studied. The dose-response curves were analyzed by a linear- quadratic model; frequency was (13.49 +/- 1.175) D + (-1.52 +/- 0.334) D2 +/- 0.048 (r2 = 0.981, D = dose in Gy). It provides the basis required for a better understanding of results which will be obtained in any further studies for biological responses of radiation using newborn orfetal mice.
Department of Veterinary Anatomy, College of Veterinary Medicine, Chonnam National University, Kwangju, Korea.
S H
SH
Kim
C Y
CY
Chung
C H
CH
Son
D000818:Animals; D000831:Animals, Newborn; D017209:Apoptosis / Q000528:radiation effects*; D002531:Cerebellum / Q000166:cytology / Q000473:pathology / Q000528:radiation effects*; D003037:Cobalt Radioisotopes; D005720:Gamma Rays; D051379:Mice; D008815:Mice, Inbred Strains; D009474:Neurons / Q000166:cytology / Q000473:pathology / Q000528:radiation effects*; D014916:Whole-Body Irradiation
D003037:Cobalt Radioisotopes