Comparative Biochemistry and Metabolism

Co-administration of an LDO.01 dose of hydrazine with 14C- methylmethionine to rats or mice results in the methylation at the 7-position of guanine in liver DNA; in the mouse, but not in the rat, methylation at the O6 - position of guanine in liver DNA also occurs. Methylation of liver DNA in only the 7-position of guanine occurs in rats and mice treated with MMH and to a much lesser extent with UDMH. Carbon dioxide production from MMH and UDMH is most active in rat liver, less active in kidney and colon and only slightly active in lung; carbon dioxide production from MMH is 1.4 to 5.5 times greater than for UDMH.