title: The microsomal metabolism of the organometallic derivatives of the group-IV elements, germanium, tin and lead.
abstract: The NADPH- and oxygen-dependent microsomal metabolism of the di-, tri- and tetra-ethyl-substituted derivatives of germanium, tin and lead was shown to give rise to ethylene as a major product and ethane as a minor product. These reactions were shown to be catalysed by the liver microsomal cytochrome P-450-dependent mono-oxygenase. Since formation of ethane and ethylene was differentially inhibited by anaerobiosis, the results suggest that at least a large portion of the ethane produced may be derived by a reductive mechanism. Triethyltin bromide in both the absence and presence of NADPH was shown to convert cytochrome P-450 into cytochrome P-420 and to affect the function of the mono-oxygenase in vitro. Tetraethyltin caused the NADPH- and time-dependent formation of cytochrome P-420, suggesting that tetraethyltin is converted into triethyltin salts in significant concentrations. The order of potency in formation of cytochrome P-420 was closely paralleled by the ability of the tin derivatives to induce microsomal lipid peroxidation in vitro.
mesh_terms: D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D004980:Ethane / Q000378:metabolism; D005030:Ethylenes / Q000378:metabolism; D005857:Germanium / Q000378:metabolism*; D066298:In Vitro Techniques; D007854:Lead / Q000378:metabolism*; D050356:Lipid Metabolism; D008297:Male; D008862:Microsomes, Liver / Q000201:enzymology / Q000378:metabolism*; D009942:Organometallic Compounds / Q000378:metabolism*; D009947:Organotin Compounds / Q000378:metabolism*; D051381:Rats; D014267:Triethyltin Compounds / Q000378:metabolism
chemical_list: D005030:Ethylenes; D009942:Organometallic Compounds; D009947:Organotin Compounds; D014267:Triethyltin Compounds; D005857:Germanium; D007854:Lead; D003577:Cytochrome P-450 Enzyme System; D004980:Ethane; C026405:bromotriethylstannane