Longo V, Mazzaccaro A, Naldi F, Gervasi P G
Istituto di Mutagenesi e Differenziamento, Consiglio Nazionale delle Ricerche, Pisa, Italy.
J Biochem Toxicol. 1991 Summer;6(2):123-8. doi: 10.1002/jbt.2570060206.
The drug-metabolizing enzymes of olfactory and respiratory epithelium of cattle were determined. The data of nasal tissues were compared to those of bovine liver. Both oxidative and nonoxidative enzyme activities were investigated. Many compounds including testosterone were used as substrates for the P450-dependent monooxygenase activities. The results demonstrated that the P450 content and all the activities assayed including reduced nicotinamide adenine dinucleotide phosphate (NADPH)-cytochrome P450 reductase were much higher in the olfactory than in the respiratory mucosa and for some activities (hexamethyl-phosphoramide and dimethylnitrosamine N-demethylase, aniline hydroxylase, and ethoxycoumarin O-deethylase) the values in the olfactory tissue were even markedly higher than those of liver. Also the activities of some nonoxidative enzymes such as glutathione S-transferase, uridine 5'-diphosphate (UDP)-glucuronyl-transferase, and epoxide hydrolase were higher in the olfactory than in the respiratory mucosa but lower than in liver. The results taken together suggest that the olfactory and respiratory epithelium of cattle, which contain in addition to a wide array of nonoxidative enzymes multiple forms of P450, can be useful and easily available tissues to study the biotransformation processes of odorants.
对牛的嗅觉和呼吸上皮组织中的药物代谢酶进行了测定。将鼻腔组织的数据与牛肝脏的数据进行了比较。对氧化酶和非氧化酶的活性均进行了研究。使用了包括睾酮在内的许多化合物作为细胞色素P450依赖性单加氧酶活性的底物。结果表明，嗅觉黏膜中的细胞色素P450含量以及所测定的所有活性（包括还原型烟酰胺腺嘌呤二核苷酸磷酸（NADPH）-细胞色素P450还原酶）均远高于呼吸黏膜，并且对于某些活性（六甲基磷酰胺和二甲基亚硝胺N-脱甲基酶、苯胺羟化酶和乙氧香豆素O-脱乙基酶），嗅觉组织中的值甚至明显高于肝脏。此外，一些非氧化酶如谷胱甘肽S-转移酶、尿苷5'-二磷酸（UDP）-葡糖醛酸基转移酶和环氧化物水解酶的活性在嗅觉黏膜中高于呼吸黏膜，但低于肝脏。综合这些结果表明，牛的嗅觉和呼吸上皮组织除了含有多种非氧化酶外还含有多种形式的细胞色素P450，是研究气味剂生物转化过程的有用且易于获取的组织。
