奥曲肽对大鼠肝星状细胞增殖的抑制作用

目的：观察奥曲肽（OCT）对肝星状细胞（HSC）Ⅰ型、Ⅲ型胶原和基质金属蛋白酶2（MMP-2）基因及蛋白表达的影响，阐明其抗肝纤维化的机制。方法：体外培养rHSC-99细胞，以不同浓度OCT作用24　h后，MTT法观察细胞增殖，ELISA法测定上清液中Ⅰ型、Ⅲ型胶原，半定量RT-PCR法检测MMP-2、Ⅰ型及Ⅲ型胶原mRNA表达。结果：与对照组比较，OCT能显著抑制体外培养的rHSC-99增殖(P<0.05)，在一定剂量范围（1～8 μg?L-1）内，随着OCT浓度升高，细胞增殖抑制率增加。与对照组比较,OCT各组细胞上清液中Ⅰ型、Ⅲ型胶原浓度明显降低(P<0.05),且Ⅰ型、Ⅲ型胶原mRNA表达水平显著降低(P<0.05)。与对照组比较，OCT组MMP-2 mRNA呈高表达（P<0.05)。结论：OCT能抑制HSC增殖，下调Ⅰ型和Ⅲ型胶原mRNA及其蛋白表达，上调MMP-2 mRNA表达水平，这可能是其抗肝纤维化作用机制之一。

Inhibitory effect of octreotide on prolieration of rat hepatic stellate cells

Objective To investigate the effects of oetreotide(OCT)on gene and protein expressions of collagen Ⅰ,collagen Ⅲ and matrix matrixmetlloproteinases 2(MMP-2)in hepatic stellate cells(HSC)in vitro,and to clarify the mechanism of its anti-hepatic fibrosis.Methods A rat hepatic stellate cell line,rHSC-99,was treated with OCT.Cell proliferation was assessed by MTT colorimetric assa(y).The contents of collagen Ⅰ,Ⅲwere examined by ELISA;RT-PCR was used to detect mRNA expressions of MMP-2,collagen Ⅰ and collagen Ⅲ.Results Compared with control group,OCT significantly inhibited rHSC-99 proliferation in vitro(P<0.05),the inhibitiory rate of cell proliferation was increased with the elevation of the OCT in a certain dose range(1-8 μg·L~(-1)).Compared with control group,the concentrations of collagen Ⅰ,Ⅲ in OCT groups were reduced significantly,the difference was significant(P<0.05);and the mRNA expressions of collagen Ⅰ and Ⅲ were also decreased(P<0.05).Compared with control group,MMP-2 mRNA was highly expressed in OCT groups(P<0.05).Conclusion OCT could inhibit the proliferation of HSC,down-regulate the expressions of collagen Ⅰ and Ⅲ mRNA and protein,and up-regulate the expression of MMP-2 mRNA.All of these biological effects of OCT on HSC are associated with recovery from liver fibrosis.