Wu. Muller et al., RELATION BETWEEN RATE OF CELL-PROLIFERATION AND FORMATION OF MICRONUCLEI AFTER COMBINED TREATMENT WITH X-RAYS AND CAFFEINE, Radiation and environmental biophysics, 32(3), 1993, pp. 239-249
Citations number
20
Categorie Soggetti
Biophysics,"Radiology,Nuclear Medicine & Medical Imaging","Environmental Sciences
We studied the effects of caffeine (2 mm), X-rays (1 Gy) and the combi
nation of both agents on cell proliferation and formation of micronucl
ei in the early stages of preimplantation mouse embryos in vitro. Two-
cell embryos were exposed to the agents shortly before division to the
4-cell stage. Proliferation and micronucleus production was monitored
every 2 h in the 4- and 8-cell stages. A rather peculiar pattern of m
icronucleus formation after radiation exposure alone was observed for
8-cell embryos: those embryos that were the first to enter the 8-cell
stage showed two to three times higher numbers of micronuclei per cell
when compared with those embryos that entered the 8-cell stage some h
ours later. Studies of the kinetics of cell proliferation and of micro
nucleus formation in 4- and 8-cell embryos and exposure to caffeine re
vealed that this result could be explained by two factors: a slight as
ynchrony in the developmental stage at the time of exposure and the le
ngth of the interval being available for repair processes. When caffei
ne was present, a third factor had to be taken into consideration: dir
ect inhibition of repair by caffeine.