These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Cytochrome P450 induction, uroporphyrinogen decarboxylase depression, porphyrin accumulation and excretion, and gender influence in a 3-week rat model of porphyria cutanea tarda.
    Author: Franklin MR, Phillips JD, Kushner JP.
    Journal: Toxicol Appl Pharmacol; 1997 Dec; 147(2):289-99. PubMed ID: 9439724.
    Abstract:
    An experimental model of porphyria cutanea tarda, consisting of depressed hepatic uroporphyrinogen decarboxylase (URO-D) activity and accumulation of highly carboxylated porphyrins in the liver, was produced in 3 weeks in Fischer 344 rats. A single administration of a polychlorinated biphenyl mixture (Aroclor 1254) to iron-loaded female rats maintained continuously on delta-aminolevulinic acid supplemented drinking water produced the porphyric state. Without iron loading, URO-D activity appeared slightly less inhibited (33% of normal vs 23% of normal) but porphyrin accumulation was dramatically less (70 vs 605 micrograms porphyrin/g liver). Similar treatment in male rats produced URO-D activities of 54 and 70% of normal with and without iron loading, respectively, and porphyrin concentrations of 76 and 17 micrograms/g. When hexachlorobenzene was substituted for Aroclor 1254 treatment in female rats, URO-D activity was 61 and 69% of normal (with and without iron loading, respectively) and liver porphyrin concentrations were 96 and 25 micrograms/g, respectively. Hexachlorobenzene did not produce significant porphyric effects in male rats. Aroclor 1254 induced CYP1A to a greater extent in females than in males and to a greater extent than hexachlorobenzene, which showed a greater propensity to induce CYP2B. Overall correlation between URO-D activity depression and porphyrin accumulation was highest when fitted to an exponential curve, indicating the importance of the extreme of the depression URO-D activity in evoking experimental porphyria cutanea tarda.
    [Abstract] [Full Text] [Related] [New Search]