Identification of N-methylprotoporphyrin IX in livers of untreated mice and mice treated with 3,5-diethoxycarbonyl-1,4-dihydrocollidine: Source of the methyl group
Administration of the porphyrogenic agent, 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) to mice, leads to the accumulation of N-methylprotoporphyrin IX in liver. This porphyrin is a potent inhibitor of ferrochelatase activity and accounts for the porphyria produced after DDC administration. The N-methylprotoporphyrin IX extracted from DDC-treated mice is primarily of one isomeric form, as shown by nuclear magnetic resonance spectroscopy. The methyl group of N-methylprotoporphyrin IX isolated from DDC-treated mice is derived mostly from the 4-methyl group of DDC. The transfer of this methyl group and its subsequent covalent attachment to protoporphyrin IX may be mediated by a form of hepatic microsomal cytochrome P-450. N-Methylprotoporphyrin IX is also found in livers of untreated mice at levels that are low but significant. © 1981.
Publication Source (Journal or Book title)
Archives of Biochemistry and Biophysics
Tephly, T., Coffman, B., Ingall, G., Zeit-Har, M., Goff, H., Tabba, H., & Smith, K. (1981). Identification of N-methylprotoporphyrin IX in livers of untreated mice and mice treated with 3,5-diethoxycarbonyl-1,4-dihydrocollidine: Source of the methyl group. Archives of Biochemistry and Biophysics, 212 (1), 120-126. https://doi.org/10.1016/0003-9861(81)90350-7