异育银鲫各组织器官中细胞色素P450药酶活性的比较

摘要

The activities and tissue distribution of cytochrome P450 drug - metabolizing enzyme were studied in liver, kidney, gill and muscle of allogynogenesis silver crucian carp Carassius auratus gibelio. Microsomal P450 and b5 contents were determined by the method of CO differential spectroscopy in liver,kidney,gill,intestine and muscle microsomes. Both cytochrome P450 and cytocorome b5 contents were found to be the maximum in liver microsome, and the minimum in muscle microsome. The activities of CYP2B, CYP3A and CYP2E were evaluated by microsomal N - demethylation of aminopyrine ( APD), erythromycin (ERND) and 4 - aniline - hydroxylation (AH) as probe specific reactions. The activities of APD ( 1. 668 ± 0. 104) and ERND (0.941 ± 0. 061 ) nmol/( min · mg)were the maximum in liver microsome, and the minimum in muscle microsome [ (0.245 ± 0.011 ), and (0. 078 ± 0.019) nmol/( min · mg)]. The maximal AH activity (0. 052 ± 0. 009)nmol/( min · mg) was observed in liver microsome, but not be detected in muscle microsome, indicating that the above -mentioned cytochrome P450 isoenzymes were available in main tissue microsoms in the crucian carp, and the APD, ERND and AH activities were different in different tissues, the maximal activities being observed in liver microsome.%对异育银鲫Carassius auratus gibelio肝胰脏、肾、鳃、肠和肌肉等组织器官中细胞色素P450(CYP450)主要药酶活性进行检测,研究其在异育银鲫各组织中的分布.结果显示:以CO还原差示光谱法测得异育银鲫肝胰脏、肾、鳃、肠、肌肉微拉体的细胞色素P450及b5含量均以肝胰脏微粒体中最高,其次为肾、鳃、肠微粒体,肌肉中最低.以氨基比林N-脱甲基、红霉素N-脱甲基、苯胺-4-羟化反应分别作为CYP2B、CYP3A和CYP2E的探针反应,测得氨基比林N-脱甲基酶(APD)及红霉素N-脱甲基酶(ERND)活性在上述组织中分布差异性类似,均表现为肝胰脏微粒体中最高,分别为(1.668±0.104)、(0.941±0.061)nmol/(min·mg),其次为肾、鳃、肠微粒体,肌肉微粒体中最低,分别为(0.245±0.011)、(0.078±0.019)nmol/(min·mg);苯胺-4-羟化酶(AH)活性以肝胰脏微粒体最高,为(0.052±0.009)nmol/(min·mg),其次为鳃微粒体,肌肉微粒体中最低,不能检出.研究表明,异育银鲫主要组织微粒体中具有细胞色素P450亚型活性,且它们在异育银鲫体内的分布和活性存在着组织和器官差异性,以肝胰脏组织中的含量和活性为最高.