Lysosomes, but not mitochondria, accumulate iron and porphyrins in porphyria induced by hexachlorobenzene

In female rats with porphyria induced by hexachlorobenzene, the amounts of non-haem iron and porphyrins in liver mitochondrial fractions were increased almost 3-fold and greater than 500-fold respectively compared with that of untreated animals. A considerable fraction of both iron and porphyrins in this fraction was shown to be located in lysosomes. Thus mitochondrial preparations, which were further depleted of lysosomes by Percoll-density-gradient centrifugation, contained 2.78 +/- 0.75 and 2.99 +/- 0.49 nmol of non-haem iron/mg of protein when isolated from the liver of control rats and hexachlorobenzene-treated rats respectively. Mitochondria isolated from the liver of hexachlorobenzene-treated animals contained a pool of iron (about 1 nmol/mg of protein) that was available for haem synthesis in vitro. This pool is similar to that previously reported for mitochondria isolated from the liver of rats with normal haem synthesis. Hexachlorobenzene treatment, therefore, does not affect the iron status of the mitochondria.