REGULATION OF CYTOCHROME P-450

大鼠致癌物诱导性和结构性基因的表达调控 细胞色素P-450检测。3-的组织特异性反应 用免疫化学方法探讨甲基胆蒽(MC)的治疗 P-450c抗体及芳烃羟基酶 (啊)活动。大鼠组织匀浆中P450c水平下降 顺序：肝、鼻咽、肺、胰腺、肾。P-450c的水平 与AHH无相关性，表明肝外AHH活性 主要来源于P-450c以外的P450形式，和/或 P-450c的比活性因组织不同而不同。归纳法 2-乙酰氨基菲对大鼠肝微粒体和核膜P450s的影响 (AAF)和MC检查。P-450c和P-450d在 每种药剂的微粒子和核膜。此外， 抗氧化剂丁基羟基甲苯增强AAF对P450c的诱导。 衰老对几种睾酮羟化P-450的影响 学习。24月龄大鼠P-450a及其受体水平升高 相关的7α羟基酶活性，但其他几种酶的水平较低 羟基酶活性。因此，尽管P-450催化的活性一般 随着年龄的增长而下降，个体P-450的表达被选择性地抑制 或被激活。

The regulation of expression of rat carcinogen-inducible and constitutive cytochromes P-450 was examined. The tissue specific response to 3- methylcholanthrene (MC) treatment was probed both immunochemically with antibodies to P-450c, and enzymatically by aryl hydrocarbon hydroxylase (AHH) activity. The level of P450c in rat tissue homogenates decreased in the order: liver, nasopharynx, lung, pancreas, kidney. The levels of P-450c and AHH did not correlate, indicating that extrahepatic AHH activity significantly derives from P450 forms other than P-450c, and/or the specific activity of P-450c varies among different tissues. The induction of rat liver microsomal and nuclear envelope P450s by 2-acetylaminofluorene (AAF) and MC was examined. P-450c and P-450d were differentially induced in microsomes and nuclear envelopes by each agent. In addition, the antioxidant butylated hydroxytoluene accentuated AAF induction of P450c. The effect of aging on several testosterone-hydroxylating P-450s was studied. Twenty-four month old rats had elevated levels of P-450a and its associated 7alpha-hydroxylase activity, but lower levels of several other hydroxylase activities. Thus, although P-450 catalyzed activities generally decline with age, expression of individual P-450s are selectively repressed or activated.