Analysis of the role of angiogenesis and non-parenchymal cells during hepatic regeneration.

我们用肝细胞生长因子拮抗剂(NK4)和血管内皮生长因子受体抑制物(sFlt-1)研究了抗血管生成对肝再生的影响。将表达NK4的腺病毒载体(Ad.NK4)或表达sFlt-1的腺病毒载体(Ad.sFlt-1)感染小鼠肝脏。70%的患者在感染后48小时行肝切除。以LacZ重组腺病毒载体(Ad.LacZ)为对照。NK4和sFlt-1的表达在感染后48h达到高峰(NK4：300 ng/ml，sFlt-1：350 ng/ml)，并持续2周。分别于术后12、24、36、48、72、120小时取残肝，评估肝再生情况。结果表明，感染Ad.NK4或Ad.sFlt-1的小鼠残肝重量的增加明显延迟。有丝分裂细胞和BrdU指数结果显示，感染Ad.NK4和Ad.sFlt-1的小鼠在肝切除后48h或36h，肝再生明显延迟。CD31免疫组织化学染色显示，Ad.NK4感染小鼠的肝窦内皮细胞生长受到抑制。Ang-1、Ang-2、Tie-1和Tie-2被认为在血管成熟过程中起关键作用。实时荧光定量聚合酶链式反应显示Ang-1、Ang-2、Tie-1、Tie-2基因的表达受到抑制，差异有统计学意义。这些结果表明，肝切除后的肝再生与血管生成密切相关。

We investigated the influence of anti-angiogenesis for hepatic regeneration using HGF antagonist (NK4) and suppressor of VEGF receptor (sFlt-1). NK4 expressing adenoviral vector (Ad.NK4) or sFlt-1 expressing adenoviral vector (Ad.sFlt-1) were infected mice liver. Seventy percent hepatectomy was performed 48 hours after infection. LacZ expressing adenoviral vector (Ad.LacZ) was used as control. Expression of Nk4 or sFlt-1 reached maximum level 48 hours after infection (NK4: 300ng/ml, sFlt-1:350ng/ml) and sustained for 2 weeks. Remnant liver was removed at 12, 24, 36, 48, 72 and 120 hrs after partial hepatectomy, and hepatic regeneration was assessed. As a result, increase of remnant hepatic weight was significantly delayed in Ad.NK4 or Ad.sFlt-1 infected mice. Results of mitotic cells and BrdU index showed significant delay of hepatic regeneration in Ad.NK4 or Ad.sFlt-1 infected mice at 48 or 36 hours after hepatectomy. Immnuhistochemical staining of CD31 showed suppression of sinusoidal endothelial cells growth in Ad.NK4 infected mice. Ang-1, Ang-2, Tie-1, and Tie-2 are considered to be crucial in the process of maturation of vessels. Real time PCR showed suppression of mRNA of Ang-1, Ang-2, Tie-1, and Tie-2 with significant difference. These results suggested that hepatic regeneration after hepatectomy closely correlates with angiogenesis.