Impact of Phospho-ELK-1 Expression in Enterocytes inBiodosimetry after Low-dose Irradiation

Abstract

Previously the higher phospho-ELK-1 (p-ELK-1) expression in enterocytes 24-96 h aftersub-lethal irradiation was measured. Therefore, purpose of this study is to examine in vivoexpression of this common ERK1/2 and JNK/SAPK target during the first hours after low-doseirradiation to assess ability of this transcriptional factor as a biodosimetric marker after the singlewhole-body irradiation. The laboratory rats were randomly divided into 12 groups and irradiatedwith whole-body gamma radiation dose of 0.25 Gy, 0.5 Gy, and 1.0 Gy. Samples of jejunum  weretaken 1 h, 2 h, 4 h, and 24 h later, the p-ELK-1 was immunohistochemically detected and thenits expression was measured by computer image analysis. A significantly increased expressionof p-ELK-1 in enterocytes was measured  1 h, 2 h, and 4 h after 0.5 Gy and 1.0 Gy irradiation,24 h after all radiation doses, respectively. Peak of p-ELK-1 expression was observed at 0.5 Gyat all time points after irradiation. The detection of p-ELK-1 might be considered as a perspectivequalitative in vivo biodosimetric marker for military purposes expressed by proliferative cells24 h after irradiation with doses from 0.25 Gy to 1.0 Gy.