Silvia C Billi de Catabbi

Learn More
In the present study, the effects of hexachlorobenzene (HCB) on lipid peroxidation and heme metabolism in the different constitutive suborgans of the kidney were determined. For this purpose, conjugated diene and malondialdehyde levels, as lipid peroxidation parameters, and porphyrin accumulation, uroporphyrinogen decarboxylase activity, and its inhibitor(More)
1. The action of hexachlorobenzene (HCB) on hepatic ferrochelatase was investigated. 2. A direct action of HCB, pentachlorophenol, porphyrins and haem on this enzyme activity was discarded. 3. In HCB porphyric liver there is probably an activator tightly bound to the enzyme. 4. Pyridoxal phosphate (PPL) may be a cofactor of ferrochelatase from both normal(More)
1. The present work undertakes a comparative study on the hexachlorobenzene (HCB) porphyria induction in female rats of Wistar and CHBBTHOM strains. The purpose was to characterize the CHBBTHOM strain with respect to the haem metabolic pathway, its regulatory mechanisms and its response to foreign drugs. 2. After 7 weeks of treatment it was observed that(More)
Hexaclorobenzene (HCB), one of the most persistent environmental pollutants, can cause a wide range of toxic effects including cancer in animals, and hepatotoxicity and porphyria both in humans and animals. In the present study, liver microsomal cytochrome P450 (CYP)-dependent arachidonic acid (AA) metabolism, hepatic PGE production, and cytosolic(More)
Hexachlorobenzene, one of the most persistent environmental pollutants, induces uroporphyria and phospholipid alterations in rat liver. Harderian glands produce a secretion that is rich in lipids and accumulate large amounts of protoporphyrin. The aim of the present study was to determine if hexachlorobenzene administration to rats affects phospholipid and(More)
1. Porphyrinogen carboxylase from the liver of normal and hexachlorobenzene porphyric rats was subjected to chemical modification using photo-oxidation with methylene blue, diethylpyrocarbonate, butane-2,3-dione, and phenylglyoxal. 2. All of these chemicals inactivated the enzyme from both sources. 3. Reversion of the diethylpyrocarbonate reaction with(More)
1. The role of histidine on the decarboxylation of porphyrinogens of 7-, 6-, and 5-COOH III brought about by porphyrinogen carboxy-lyase (PCL) was studied. 2. For this purpose hepatic PCL from normal and hexachlorobenzene (HCB) treated rats were modified with diethylpyrocarbonate. 3. The results indicated that the enzyme from both normal and porphytic(More)
A great deal of information concerning the effects of hexachlorobenzene on the haem metabolic pathway has been obtained but little is known about the effects of the drug on lipid metabolism. Consequently, the time course of phospholipid metabolism alteration caused by this xenobiotic was evaluated as related to changes in porphyrin metabolism with the aim(More)
Porphyrinogen carboxylyase from normal rat liver was subjected to purification methods. Two different purification protocols were used. In both cases, the initial steps consisted in obtaining a liver homogenate, followed by centrifugation, salt precipitation and phosphate gel absorption. Scheme I consisted in then submitted the preparation to(More)
Hexachlorobenzene (HCB) alters phospholipid and heme metabolisms in the liver and Harderian gland. The effects of HCB on phospholipid metabolism, in an organ considered to be non-responsive to its porphyrinogenic effects, remain to be studied. Therefore, as the brain is an organ with this feature, this paper analyzes the effects of HCB on brain phospholipid(More)