TY - JOUR T1 - Effects of L-histidine on hydrogen peroxide-induced DNA damage and cytotoxicity in cultured mammalian cells. JF - Molecular Pharmacology JO - Mol Pharmacol SP - 969 LP - 974 VL - 41 IS - 5 AU - O Cantoni AU - P Sestili AU - A Guidarelli AU - P U Giacomoni AU - F Cattabeni Y1 - 1992/05/01 UR - http://molpharm.aspetjournals.org/content/41/5/969.abstract N2 - L-Histidine markedly increased the growth- and DNA synthesis-inhibitory effects elicited by hydrogen peroxide in cultured Chinese hamster ovary cells. DNA single-strand breakage was also higher in the presence of the amino acid and, in addition, these breaks were characterized by a slower rate of repair, compared with that of the breaks generated by the oxidant alone. In the presence of L-histidine, hydrogen peroxide also produced DNA double-strand breakage, a lesion that cannot be detected in cells treated with even exceedingly high concentrations of the oxidant alone. Data reported herein suggest that the L-histidine-mediated increase of the cytotoxic response of cultured Chinese hamster ovary cells to hydrogen peroxide may be at least partially dependent on the formation of DNA double-strand breaks. ER -