Expression of activated ATF-2, CREB and c-Myc in rat colon transversum after whole-body gamma-irradiation and its contribution to pathogenesis and biodosimetry.
OBJECTIVE
The purpose of our study is to examine phospho-ATF-2(Thr-69/71) (phospho-activating transcription factor-2, p-ATF-2), phospho-CREB(Ser-133) (phospho-cAMP response binding element protein, p-CREB), and phospho-c-Myc(Thr-58/Ser-62) (phosho-myelocytomatosis protooncogene, p-c-Myc) expression in irradiated rat colon transversum.


METHODS
Male Wistar rats were randomly divided to 28 groups and irradiated with whole-body gamma-radiation of 0, 0.25, 0.5, 0.75, 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 Gy. Samples were taken 4 and 24 hours after the irradiation, immunohistochemically stained. P-ATF-2, p-CREB, and p-c-Myc expression was measured.


RESULTS
We measured increased cytoplasmatic p-ATF-2 expression 4 hours after irradiation by 0.25 - 1, 10 Gy and 24 hours after irradiation by 0.5 - 1, 10 Gy. Increased cytoplasmatic p-CREB expression was found 4 hours after irradiation by 0.25 - 1, 9, 10 Gy and 24 hours after irradiation by 0.25 - 1, 4, 10 Gy. Increased p-c-Myc cytoplasmatic expression was found 4 hours after irradiation by 0.25, 0.75, 4, 5 Gy and 24 hours after irradiation by 0.75, 1, 10 Gy. Nuclear p-ATF-2, p-CREB, and p-c-Myc expressions were similar to their cytoplasmatic expressions.


CONCLUSIONS
The detection of p-ATF-2 and p-CREB might be considered as a perspective biodosimetric tool for irradiated enterocytes in vivo. The use of p-c-Myc appears to be controversial due to the ambivalent expression values.
Pejchal
Jaroslav
J
Center of Advanced Studies, Faculty of Military Health Science, University of Defense, Trebesska 1575, 500 01, Hradec Kralove, Czech Republic. jaroslav.pejchal@seznam.cz
Osterreicher
Jan
J
Vilasová
Zdenka
Z
Tichý
Ales
A
Vávrová
Jirina
J
D051698:Activating Transcription Factor 2 / Q000378:metabolism*; D000818:Animals; D001681:Biological Assay / Q000379:methods*; D001822:Body Burden; D003106:Colon / Q000378:metabolism* / Q000528:radiation effects*; D017362:Cyclic AMP Response Element-Binding Protein / Q000378:metabolism*; D005720:Gamma Rays; D015870:Gene Expression / Q000528:radiation effects; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012062:Relative Biological Effectiveness; D014915:Whole-Body Counting / Q000379:methods*; D014916:Whole-Body Irradiation
D051698:Activating Transcription Factor 2; D017362:Cyclic AMP Response Element-Binding Protein