Jordan J T, Killenberg P G
Am J Physiol. 1980 May;238(5):G429-33. doi: 10.1152/ajpgi.1980.238.5.G429.
In vitro levels of enzyme activity were measured in liver from fetal and developing hamsters to study the fetal immaturity and postnatal development of bile acid conjugation and sulfation. Sulfation and conjugation were measured in the same animals. Partial reactions of bile acid conjugation were assayed independently; sulfation of conjugated and unconjugated lithocholate was measured separately. From 3 days before to 3 days after birth, specific activity for sulfation of lithocholate and lithocholate conjugates was similar; lithocholate sulfation was 80% of adult levels. In older hamsters, specific activity for sulfation of lithocholate conjugates was significantly higher than that for lithocholate. Specific activities of both partial reactions of bile acid conjugation were 12% of adult levels from 3 days before to 3 days after birth. Thereafter both activities increased together; the ratio of glycine to taurine-dependent conjugation was similar at all ages. The data suggest early development of a separate mechanism for lithocholate sulfation. Enzymes catalyzing bile acid conjugation and sulfation of bile acid conjugates exhibit maximal development after birth.
为研究胆汁酸结合和硫酸化的胎儿期不成熟及出生后发育情况，测定了胎儿及发育中小仓鼠肝脏的体外酶活性水平。在同一动物中测定了硫酸化和结合情况。分别独立测定胆汁酸结合的部分反应；分别测定结合型和未结合型石胆酸的硫酸化情况。从出生前3天到出生后3天，石胆酸及其结合物的硫酸化比活性相似；石胆酸硫酸化是成年水平的80%。在较大的仓鼠中，石胆酸结合物的硫酸化比活性显著高于石胆酸。从出生前3天到出生后3天，胆汁酸结合的两个部分反应的比活性均为成年水平的12%。此后，两种活性共同增加；甘氨酸与牛磺酸依赖性结合的比例在所有年龄段都相似。数据表明石胆酸硫酸化存在一种独立机制的早期发育。催化胆汁酸结合和胆汁酸结合物硫酸化的酶在出生后表现出最大程度的发育。
