The effect of dexamethasone, insulin and triiodothyronine on microsomal NADPH-cytochrome-c (P-450) reductase in primary cultures of isolated hepatocytes.
The effect of dexamethasone, insulin and triiodothyronine on microsomal NADPH-cytochrome-c (P-450) reductase in primary cultures of isolated hepatocytes.
复制标题
地塞米松、胰岛素和三碘甲状腺原氨酸对分离肝细胞原代培养物中微粒体 NADPH-细胞色素-c (P-450) 还原酶的影响。
DOI：
10.1016/0167-4889(87)90050-4
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发表时间：
1987
期刊：
影响因子：
--
通讯作者：
Galivan,J
中科院分区：
文献类型：
--
作者：
vanderHoeven,T;Galivan,J
NADPH-细胞色素-c（P-450）还原酶是一种黄素蛋白，是肝微粒体多底物单加氧酶的组成部分，并催化电子从NADPH转移到细胞色素-450。在含有胰岛素、地塞米松和三碘甲状腺原氨酸的Waymouth MB752/1培养基中培养48小时，研究了nadph -细胞色素还原酶活性和蛋白质的激素调节。nadph -细胞色素还原酶、酪氨酸转氨酶和苹果酸脱氢酶活性对地塞米松和三碘甲状腺原氨酸处理的反应没有相似性。在缺乏激素的情况下，大约65%的原始nadph -细胞色素-还原酶活性和免疫化学染色技术估计的蛋白质被保留。在胰岛素（10.0 mU/ml）或地塞米松（100 nM）中单独培养肝细胞，而不是三碘甲状腺原氨酸，可以改善还原酶活性和蛋白质的保留。只有在胰岛素、三碘甲状腺原氨酸和地塞米松中培养肝细胞，才能使nadph -细胞色素还原酶活性和蛋白维持在原有水平。发现单独地塞米松可以持续增强还原酶蛋白的保留，但不能增强还原酶活性，其水平与刚分离的肝细胞大致相同。结果表明，在地塞米松、胰岛素和三碘甲状腺原氨酸的作用下，离体肝细胞微粒体nadph -细胞色素-还原酶活性和蛋白水平维持在原有水平。
NADPH-cytochrome-c(P-450) reductase, a flavoprotein, is a constituent of the hepatic microsomal polysubstrate monooxygenase and catalyzes the transfer of electrons from NADPH to cytochromeP-450. The hormonal regulation of NADPH-cytochrome-creductase activity and protein has been examined in insolated hepatocytes cultured as monolayers for 48 h in Waymouth's MB752/1 medium fortified with insulin, dexamethasone and triiodothyronine. No similarity between the response of NADPH-cytochrome-creductase and of tyrosine aminotransferase and malate dehydrogenase activity to dexamethasone and triiodothyronine treatment could be detected. In the absence of hormones about 65% of the original NADPH-cytochrome-creductase activity and protein estimated by the immunochemical staining technique was retained. Culture of hepatocytes in insulin (10.0 mU/ml) or dexamethasone (100 nM) alone but not triiodothyronine improved the retention of reductase activity and protein. Only when hepatocytes were cultured in insulin, triiodothyronine and dexamethasone could NADPH-cytochrome-creductase activity and protein be maintained at the original level. Dexamethasone alone was found to enhance consistently retention of reductase protein, but not reductase activity, to approximately the same level as in freshly isolated hepatocytes. The results suggest that microsomal NADPH-cytochrome-creductase activity and protein can be maintained in isolated hepatocytes at the original level by culturing the cells in dexamethasone, insulin and triiodothyronine.