The effect of the timing of prenatal X-irradiation on Purkinje cell numbers in rat cerebellum.
Exposure of the developing brain to X-irradiation in utero is known to cause various deleterious consequences. We have previously reported the effects of prenatal X-irradiation on the development of the cerebral cortex in rats. We have now extended this study to examine the effects of such X-irradiation on the development of the cerebellum. Wistar rats were exposed to 1.5 Gy X-irradiation either on days 14, 15 or 16 of gestation (E14, E15, E16). Sham-irradiated animals were used as controls. At seven postnatal weeks of age, male rats from each group were deeply anesthetized and killed by intracardiac perfusion with 2.5% glutaraldehyde in 0.1 M phosphate buffer. The unbiased stereological procedure known as the fractionator method was used to estimate the total number of Purkinje cells in the cerebellum of each animal. Body and cerebellar weights from E14 and E15, but not E16 irradiated rats showed significant deficits compared to control animals. Rats irradiated on E16 and control rats had about 285100-304800 Purkinje cells in the cerebellum. There was no significant difference between these values. However, E14 and E15 irradiated animals had about 117500 and 196300 Purkinje cells, respectively. These estimates were significantly different from those observed in both control and E16 irradiated rats. Given that the phase of division of Purkinje cell progenitors is mainly between E14-E15 and the phase of differentiation and migration is between E16-E20, it is concluded that the vulnerable period of the Purkinje cells to X-irradiation closely overlaps the phase of division of progenitors.
Li
Hong Peng
HP
Department of Anatomy, Faculty of Medicine, Kagawa Medical University, 1750-1 Ikenobe, Miki-cho, Kagawa 761-0793, Japan.
Miki
Takanori
T
Gu
He
H
Satriotomo
Irawan
I
Mastumoto
Yoshiki
Y
Kuma
Hiromi
H
Gonzalez
Daniel
D
Bedi
Kuldip S
KS
Suwaki
Hiroshi
H
Takeuchi
Yoshiki
Y
D000818:Animals; D000831:Animals, Newborn; D001835:Body Weight / Q000502:physiology / Q000528:radiation effects; D002452:Cell Count; D002454:Cell Differentiation / Q000502:physiology / Q000528:radiation effects*; D002455:Cell Division / Q000502:physiology / Q000528:radiation effects*; D002465:Cell Movement / Q000502:physiology / Q000528:radiation effects; D002531:Cerebellum / Q000166:cytology / Q000254:growth & development* / Q000528:radiation effects*; D005260:Female; D008297:Male; D009929:Organ Size / Q000502:physiology / Q000528:radiation effects; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011689:Purkinje Cells / Q000166:cytology / Q000502:physiology / Q000528:radiation effects*; D051381:Rats; D017208:Rats, Wistar; D013234:Stem Cells / Q000166:cytology / Q000502:physiology / Q000528:radiation effects*; D014965:X-Rays / Q000009:adverse effects*