Detoxification of drugs and

MFO). Similar MFO microsomal redox systems operate for the metabolic detoxification of drugs and some waste products (Section 6.4). 

Scheme 3, The metabolism and detoxification of drugs and environmental chemicals via the mixed function oxygenase, glutathione transferase, and epoxide hydrase pathways.

Christoph Handschin describes the role of nuclear receptors, more specifically the pregnane X receptor and the constitutive androstane receptor, in the induction of drug metabolism and detoxification of drugs and other xenobiotics. 

Merk, H.F. Jugert, F.K. Metabolic activation and detoxification of drugs and xenobiotica by the skin. In Dermal and Transdermal Drug Delivery—New Insigts and Perspectives Gurny, R., Teubner, A., Eds. Wiss.Verl. Ges. Stuttgart, 1993 91-100. 

Flavin-containing monooxygenases (FMOs) are a class of flavin monooxygenases that contain tightly boxmd FAD and require NADPH as coenzyme. These enzymes catalyze the monooxygenation of different heteroatoms, with the natural role of participating in the detoxification of drugs and xenobiotics [22,53]. Most of the FMOs are membrane associated, which makes it difficult to obtain them for further application. The human proteome contains five FMO isoforms, FMOl-5. FMOS seems to be the dominant enzyme in the himian body. 

Synthesis of tatty acids, cholesterol, and other steroids, metabolic detoxification of drugs, poisons, end NHa... 

All tissues except mature red blood cells are able to manufacture haem for use in the respiratory cytochrome proteins of the electron transport chain. However, the liver is an especially important site of haem synthesis because it (a) is a major organ of erythropoiesis in utero and (b) haem-containing cytochrome-P450 (CYP-450) enzymes play significant roles in hepatic detoxification of drugs, toxins and endogenous waste products (Section 6.4). 

The metabolism of drugs and agents does not always lead to detoxification occasionally, the metabolites are toxicologically more potent. Some examples of this are sulfamethazine, which is metabolized to /V4-acetylsulfamethazine, and aminopyrine, with 4-aminoantipyrine as its metabolite. 

CYP enzymes play a role in both the detoxification of compounds and the bioactivation of drugs, pesticides and many environmental pollutants into carcinogens, mutagens and cytotoxins. Thus, the P450 superfamily of enzymes is important from medical, pharmaceutical, and agrochemical perspectives. 

Hepatocytes growing in microcarrier systems are used for the study of liver failure and drug metabolism. Transplantation experiments of hepatocytes grown on microcarriers showed detoxification of ammonium and reduction of bilirubin concentrations after induced acute liver failure (Nagaki et aL, 1990). Furthermore, co-cultivation assays using hepatocytes and Balb/c 3T3 fibroblasts as target cells have been applied to analyse the metabolism-mediated toxicity of xenobiotics in vitro (Voss Seibert, 1992). 

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