M. Wojewodzka et al., EFFECT OF SIGNAL-TRANSDUCTION INHIBITION IN ADAPTED LYMPHOCYTES - MICRONUCLEI FREQUENCY AND DNA-REPAIR, International journal of radiation biology, 71(3), 1997, pp. 245-252
Citations number
29
Categorie Soggetti
Radiology,Nuclear Medicine & Medical Imaging","Nuclear Sciences & Tecnology
Irradiation of human lymphocytes (1 cGy X rays, 37 degrees C) or their
treatment with 10 mu M hydrogen peroxide (30 min at 37 degrees C) evo
ked a ca 30% decrease in the frequency of micronuclei upon subsequent
X-irradiation (1.5 Gy). The response was reflected in a lower micronuc
lei frequency, but no change in DNA repair rate was observed as measur
ed by the comet assay, directly after the challenge dose. Treatment of
lymphocytes with staurosporine, an inhibitor of protein kinases, or w
ith TMB-8, a calcium antagonist, carried out in parallel with the adap
tive dose prevented the development of the adaptive response measured
as micronuclei frequency. In lymphocytes that were staurosporine- or T
MB-8-treated and irradiated under adaptive conditions showed that the
rate of DNA repair was not changed. We conclude that treatment with ag
ents that interfere with the transduction of the signal triggered by t
he low dose prevents the development of the adaptive response induced
by X rays or hydrogen peroxide. Lower chromosome damage revealed by th
e cytokinesis block-micronuclei test in the adapted lymphocytes is unr
elated to DNA repair rate as measured by comet assay.