Ligation of portal vein branch induces DNA polymerases alpha, delta, and epsilon in nonligated lobes
Ligation of portal vein branch induces DNA polymerases alpha, delta, and epsilon in nonligated lobes
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DOI：
10.1006/jsre.1996.0337
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发表时间：
1996-09-01
影响因子：
2.2
通讯作者：
Yoshida, S
中科院分区：
文献类型：
--
作者：
Takeuchi, E;Nimura, Y;Yoshida, S
结扎供应70%大鼠肝脏的门静脉分支引起非结扎肝叶的代偿性肥大，并伴随结扎肝叶的萎缩。为了阐明这种反应的机制，研究了门静脉分支结扎后非结扎肝叶中DNA聚合酶α、δ、γ和增殖细胞核抗原（PCNA）的诱导。将诱导模式与70%肝部分切除后的肝再生进行比较。用5 mM KCl（低盐提取物），然后用600 mM KCl（高盐提取物）提取肝脏中的DNA聚合酶α、δ和β。在羟基磷灰石柱上部分分离低盐提取物中的DNA聚合酶α、δ和β并定量。门静脉分支结扎后24小时内，非结扎叶中的所有酶活性开始增加，并在48小时达到最高水平。这些模式与部分肝切除术后的残肝非常相似。在低盐提取物中，DNA聚合酶δ和β-淀粉酶是突出的，而在高盐提取物中，主要是DNA聚合酶α和β-淀粉酶的一些活性被恢复。门静脉分支结扎和部分肝切除术后，PCNA也诱导，在48小时达到最高水平。从DNA聚合酶和PCNA的类似变化，我们的数据表明，门静脉分支结扎诱导肝细胞增殖的非结扎叶的方式类似于部分肝切除术。(C)出版社：Academic Press，Inc.
Ligation of a portal vein branch supplying 70% of the rat liver causes compensatory hypertrophy of the nonligated hepatic lobes with concomitant atrophy of the ligated lobes, To elucidate the mechanism of this response, the induction of the replication enzymes DNA polymerases alpha, delta, epsilon, as well as proliferating cell nuclear antigen (PCNA), were investigated in nonligated lobes after portal branch ligation. The induction patterns were compared with the well studied liver regeneration after 70% partial hepatectomy. DNA polymerases alpha, delta, and epsilon in the liver were extracted with 5 mM KCI (low-salt extract), then with 600 mM KCl (high-salt extract). DNA polymerases alpha, delta, and epsilon in low-salt extract were partially separated on a hydroxyapatite column and quantified. All enzyme activities in the nonligated lobes started to increase within 24 hr and reached maximum levels by 48 hr after portal branch ligation. These patterns were quite similar to those obtained with the remnant liver after partial hepatectomy. In low-salt extract, DNA polymerase delta and epsilon were prominent, while, in high-salt extract, largely DNA polymerases alpha and some activity of epsilon were recovered. PCNA was also induced after both portal branch ligation and partial hepatectomy, reaching maximum levels at 48 hr. From the similar changes in DNA polymerases and PCNA, our data indicate that portal branch ligation induces hepatocyte proliferation in the nonligated lobes in a way similar to partial hepatectomy. (C) 1996 Academic Press, Inc.