Metabolism of high density lipoprotein lipids by the rat liver: evidence for participation of hepatic lipase in the uptake of cholesteryl ester.
Metabolism of high density lipoprotein lipids by the rat liver: evidence for participation of hepatic lipase in the uptake of cholesteryl ester.
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大鼠肝脏对高密度脂蛋白脂质的代谢：肝脂肪酶参与胆固醇酯摄取的证据。
作者：
H. Kadowaki;G. Patton;S. Robins
为了确定肝脂肪酶在高密度脂蛋白（HDL）甘油三酯、胆固醇酯和磷脂的肝脏摄取和代谢中的作用，用[3 H]三油酸甘油酯和[14 C]胆固醇油酸酯或棕榈酰-[14 C]亚油酰磷脂酰胆碱放射性标记的重建HDL（rHDL）灌注离体大鼠肝脏。将放射性标记的rHDL推注到门静脉中，并使用非再循环灌注系统灌注肝脏5分钟。使用肝脏中rHDL三油酸甘油酯作为完整三油酸甘油酯的回收率来确定肝脏中剩余的未代谢rHDL的量。校正肝脏中剩余的未代谢rHDL量后，约30%的rHDL三油酸甘油酯水解，其中19%在肝脏中回收，11%在灌注液中回收。此外，约7%的rHDL磷脂酰胆碱被水解为溶血磷脂酰胆碱，所有这些都在灌注液中回收。虽然rHDL胆固醇油酸酯没有水解，但约30%的胆固醇油酸酯被肝脏吸收。用肝素预灌注肝脏以消耗肝脏的肝脂肪酶导致rHDL三油酸甘油酯水解减少约70%，rHDL胆固醇油酸酯摄取减少约75%。虽然肝脂肪酶水解甘油三酯和磷脂酰胆碱，从rHDL中消除三油酸甘油酯对rHDL胆固醇油酸酯的摄取没有影响，但用不可水解的磷脂酰胆碱二醚替代rHDL磷脂酰胆碱导致胆固醇油酸酯摄取减少87%。这些结果表明，肝脂肪酶是必要的HDL甘油三酯和胆固醇酯的肝摄取和胆固醇酯的摄取是不依赖于HDL甘油三酯的水解，但依赖于HDL磷脂的水解。
In order to determine the role of hepatic lipase in the hepatic uptake and metabolism of high density lipoprotein (HDL) triglycerides, cholesteryl esters, and phospholipids, isolated rat livers were perfused with a reconstituted HDL (rHDL) radiolabeled with [3H]triolein and [14C]cholesteryl oleate or palmitoyl-[14C]linoleoyl phosphatidylcholine. A bolus of radiolabeled rHDL was injected into the portal vein and livers were perfused for 5 min using a nonrecirculating perfusion system. Recovery of rHDL triolein in the liver as intact triolein was used to determine the amount of unmetabolized rHDL remaining in the liver. After correcting for the amount of unmetabolized rHDL remaining in the liver, about 30% of the rHDL triolein was hydrolyzed of which 19% was recovered in the liver and 11% in the perfusate. Moreover, about 7% of the rHDL phosphatidylcholine was hydrolyzed to lysophosphatidylcholine, all of which was recovered in the perfusate. Although there was no hydrolysis of rHDL cholesteryl oleate, about 30% of the cholesteryl oleate was taken up by the liver. Preperfusion of the liver with heparin to deplete the liver of hepatic lipase resulted in about a 70% reduction in rHDL triolein hydrolysis and about a 75% reduction in rHDL cholesteryl oleate uptake. Although hepatic lipase hydrolyzes both triglycerides and phosphatidylcholines, elimination of the triolein from rHDL had no effect on the uptake of rHDL cholesteryl oleate, but replacement of the rHDL phosphatidylcholine with a nonhydrolyzable phosphatidylcholine diether resulted in an 87% reduction in cholesteryl oleate uptake. These results indicate that hepatic lipase is necessary for the hepatic uptake of both HDL triglycerides and cholesteryl esters and that the uptake of cholesteryl esters is not dependent on the hydrolysis of HDL triglycerides but is dependent on the hydrolysis of HDL phospholipids.
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四硝基甲烷修饰人高密度脂蛋白 (HDL3) 及其与离体大鼠肝质膜结合的影响。
影响因子：
6.5
作者：
Chacko,GK
通讯作者：
Chacko,GK
疏水性对大鼠血浆磷脂酰胆碱醚标记的高密度脂蛋白周转的影响。
影响因子：
6.5
作者：
Pownall,HJ;Hickson-Bick,D;Massey,JB
通讯作者：
Massey,JB
影响因子：
15.9
作者：
BIESBROECK, R;ORAM, JF;BIERMAN, EL
通讯作者：
BIERMAN, EL
DOI：
10.1016/0005-2760(83)90237-0
发表时间：
1983-06
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
Y. Stein;Y. Dabach;G. Hollander;G. Halperin;Olga Stein
通讯作者：
Y. Stein;Y. Dabach;G. Hollander;G. Halperin;Olga Stein
DOI：
10.1016/s0021-9258(18)61523-6
发表时间：
1987-02
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
R. Pittman;C. Glass;D. Atkinson;D. Small
通讯作者：
R. Pittman;C. Glass;D. Atkinson;D. Small