Abstract
Radiation-induced mutations were studied in vivo with a transgenic mouse called HITEC, which carries the rpsL gene as a reporter for mutations. Although we had previously investigated the increase in mutation frequency caused by ~5 Gy of gamma-rays in mouse liver, no obvious increase in mutation frequency was observed due to a high background mutation frequency. We therefore performed a partial hepatectomy to amplify the mutation frequency. HITEC mice were irradiated with 5 Gy of gamma rays before hepatectomy and the remnant liver was resected after hepatectomy. The mutation frequency was then analyzed. In mice in which hepatectomy was done 2 days after irradiation and the remnant liver was resected 10 days after hepatectomy, the mutation frequency was approximately two-fold higher. In mice in which hepatectomy was done 10 days after irradiation and the remnant liver was resected 2 or 10 days after hepatectomy, the mutation frequency was two to three times greater. These results indicate that partial hepatectomy increases the frequency of radiation-induced mutations. [J Radiat Res 44:414 (2003)]
