HSS+EGF治疗醋氨酚所致暴发性肝坏死的实验研究

肝细胞的增生受体液因子调节,一类是抑制增生的α_1巨球蛋白称肝抑素(Chal-on),另一类是刺激肝脏细胞增生因子包括外源性刺激因子如胰岛素、胰高血糖素、

Growth induction of hepatic stimulator substance in hepatocytes through its regulation on EGF receptors

The cytosolic liver-specific growth factor-hepatic stimulator substance (HSS) has been shown to be able to amplify the rat hepatocyte proliferation responded to EGF. In order to get more insight into the mechanism, the regulatory effect of HSS on EGF-receptor(EGF-R) and the receptor phosphorylation at molecular level was studied. HSS partially purified from weanling rat liver was given to cultured hepatocytes and its influence on EGF-R specific binding and internalization as well as mRNA expression were investigated. The results showed that preincubation of hepatocytes with HSS could lead to an increase in [125I]-EGF binding to its receptors and inhibit EGFinduced receptor down-regulation. Furthermore, the overexpression of EGF-R mRNA stimulated by HSS was seen during 2-12 h after the incubation. Additionally, it was demonstrated with human hepatoma sMMC-7721 cells in Western blot that the EGF-R expression and the receptor autophosphorylation were increased with dose/timedependency after HSS treatment. These results strongly suggest that the mechanism of HSS action on hepatocyte growth might be related to its modulation on EGF-R and receptor-mediated signaling transduction.

肝再生刺激因子、表皮生长因子对肝细胞的作用

目的：观察肝再生刺激因子(HSS）及表皮生长因子（EGF)对肝细胞增殖再生作用合适剂量及其联合效应，并推测HSS作用时相。方法：以~3HTdR掺入法检测细胞DNA增殖；体外原代大鼠肝细胞培养不同时间加入HSS,MTT法检测细胞生长状况。结果与结论：1.HSS（≤100μg／ml)和EGF（≤100ng／ml）对肝衍生细胞均有显著刺激作用（P＜0.01）,并存在剂量关系，但剂量过大，刺激作用反而下降。2.HSS、EGF存在协同作用，原代肝细胞、肝癌细胞株（SMMC-7721、BEL-7402）体外培养48h后，经(~3H）TdR掺入法检测cpm值分别为各自对照组的5.94、2.98和3.36倍。3.体外培养原代大鼠肝细胞，于贴壁后Oh.20h加入HSS其刺激作用较40h组显著.提示HSS可能主要作用于肝细胞再生G1/S期。