Effect of hormone treatment on spontaneous and radiation-induced chromosomal breakage in normal and dwarf mice

Abstract

Treatment of dwarf mice with growth hormone, insulin and testosterone had no effect on the spontaneous frequencies of micronuclei (MN) in bone-marrow cells, whereas thyroxine decreased these frequencies. The induction of MN by X-rays and mitomycin C was significantly lower in dwarf mice than in normal mice. Treatment with thyroxine plus growth hormone restored normal radiosensitivity in dwarfs.