The developmental expression of acyl-coenzyme A:cholesterol acyltransferase in the yolk sac membrane, liver, and intestine of developing embryos and posthatch turkeys
The developmental expression of acyl-coenzyme A:cholesterol acyltransferase in the yolk sac membrane, liver, and intestine of developing embryos and posthatch turkeys
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DOI：
10.1093/ps/79.10.1460
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发表时间：
2000-10-01
期刊：
影响因子：
4.4
通讯作者：
Lilburn, MS
中科院分区：
文献类型：
--
作者：
Ding, ST;Lilburn, MS
酰基辅酶A：胆固醇酰基转移酶(ACAT)催化游离胆固醇和脂肪酰基辅酶A生成胆固醇酯(CE)。本实验研究了火鸡胚胎发育和早期生长过程中卵黄囊膜、肝脏和肠道中ACAT活性的个体发育。从胚胎第13天(第13天)到出生后第6天(第6天)，每隔3天收集一次组织样本，测定ACAT活性。卵黄囊膜中的ACAT活性(每分钟微粒体蛋白含量)从发育第13天的840pmol上升到发育第2 2天的2,497pmol，随后在发育第3天降至极低水平。在发育到第22天时，卵黄囊膜中的酶活性很高，同时卵黄囊膜内形成了大量的CE。肝脏ACAT活性从第13天的60pmol上升到第242天和第3天的243fmol，然后在第6天下降到130pmol，反映了肝脏CE浓度的峰值。这表明，即使在孵化过程中，肝脏在脂肪代谢中也发挥着重要作用。肠道ACAT比活性从14pmol(ED16)上升到44pmol(ED25)，然后下降到23pmoL(ED28)，到PD 6后没有进一步下降。然而，从ED16到PD 6，肠道ACAT总活性(每肠pmoL/min)增加。这种活性的增加表明在孵化过程中和孵化后不久，总的胆固醇酯化能力增加。
Acyl-coenzyme A:cholesterol acyltransferase (ACAT) catalyzes the formation of cholesterol esters (CE) from free cholesterol and fatty acyl-coenzyme A. This experiment was conducted to study the ontogeny of ACAT activity in the yolk sac membrane, liver, and intestine during embryonic development and early posthatch growth of turkeys. The ACAT activity was measured On tissue samples collected at 3-d intervals from embryonic Day (ED 13) 13 through 6 d posthatch (PD 6). The ACAT activity (pmol/mg microsomal protein per min) in the yolk sac membrane increased form 840 pmol at ED 13 to 2,497 pmol at ED 22, and subsequently declined to a very low level by PD 3. The high level of enzyme activity at ED 22 is concomitant with the large quantity of CE formed within the yolk sac membrane at this developmental age. Liver ACAT activity increased from 60 pmol at ED 13 to 242 to 243 Fmol at ED 25 and PD 3, followed by a decline to 130 pmol by PD 6, mirroring the peak in hepatic CE concentration. This suggests that even during incubation, the liver plays a significant role in lipid metabolism. Intestinal ACAT specific activity increased from 14 pmol (ED 16) to 44 pmol (ED 25), and then declined to 23 pmol by hatch (ED 28), with no further decline through PD 6. Total intestinal ACAT activity (pmol per intestine/min) increased, however, from ED 16 through PD 6. This increase in activity suggests that the total capacity for cholesterol esterification increases during the course of incubation and shortly after hatching.