Metabolism of tetraorganolead compounds by rat-liver microsomal mono-oxygenase. II. Enzymic dealkylation of tetraethyl lead
| Autor: | U. Schröder, D. Ferreira Da Silva, H. Diehl |
|---|---|
| Rok vydání: | 1983 |
| Předmět: |
Male
Cytochrome Stereochemistry Health Toxicology and Mutagenesis chemistry.chemical_element Alkylation Toxicology Biochemistry Oxygen Medicinal chemistry Cytochrome P-450 Enzyme System Organometallic Compounds Animals Tetraethyl Lead Pharmacology biology Substrate (chemistry) Rats Inbred Strains General Medicine Metabolism Rats Kinetics chemistry Dealkylation Rat liver Enzyme Induction Phenobarbital Microsome biology.protein Microsomes Liver Oxygenases Methylcholanthrene |
| Zdroj: | Xenobiotica; the fate of foreign compounds in biological systems. 13(10) |
| ISSN: | 0049-8254 |
| Popis: | 1. The biological degradation of tetraethyl lead to the triethyl lead cation by rat-liver microsomes from untreated, phenobarbital-pretreated and methylcholanthrene-pretreated rats has been studied; NADPH and oxygen are essential.2. The reaction is inhibited by CO and can be reactivated in the presence of O2 by irradiation with u.v. light with a max. at 450nm.3. Substrate binding to cytochrome P-450 is of type 1.4. Apparent Km values for triethyl lead formation in microsomes were determined. The highest activities (i.e. about 2 nmol triethyl lead per nmol cytochrome P-450 per min) and the lowest apparent Km values (i.e. 7 × 10-6 M) are found in microsomes from methylcholanthrene-pretreated rats.5. In microsomes from control and phenobarbital-pretreated rats Ks values from substrate-binding studies (about 2 × 10-6M) are one order of magnitude lower than the apparent Km values (3 × 10-5 M). |
| Databáze: | OpenAIRE |
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