中文摘要：

目的：研究TNF-α对内皮细胞与周细胞PDGF—B／PDGFR—β表达的作用。方法：常规剂量100ug／L以及大剂量2450ug／L TNF-α作用于培养的视网膜微血管内皮细胞、周细胞，通过免疫组化、Western Blot、RT—PCR检测PDGF—B／PDGFR—β表达。结果：内皮细胞组大剂量TNF-α组，PDGF—B表达显著下调，8h表达开始出现下调，在12h，PDGF-B的表达量为原来的39％；在人视网膜微血管周细胞组，与对照组相比，常规TNF-α剂量组PDGFR-β表达并未出现显著改变；大剂量TNF-α组，与对照组相比，PDGFR-β表达在12h下调为45％。结论：TNF-α可引起内皮细胞与周细胞PDGF—B／PDGFR-β表达降低。

英文摘要：

AIM： To investigate alterations of the gene expression of PDGF-B and PDGFR-β of bovine retinal microvessel endothelial cells and pericytes induced by TNF-α. METHODS： Retinal microvessle endothelial cells and pericytes were isolated and reversed transcriptase polymerase chain reaction （RT-PCR） and western blot analyses were performed to determine the mRNA and protein content for PDGF-B and PDGFR-β induced by different concentration of TNF-α. RESULTS： By semi-quantity RT-PCR, for the endothelial cells groups, the expressions of PDGF-B were downregulated about 39% at 12h in the large dosage of TNF-α group （2 450ug/L） ; For pericytes groups, the expression of PDGFR-β did not show significant changes in the routine dosage of TNF-α group （vs control ）, the expressions of PDGFR-β were down-regulated about 45% at 12h in the large dosage of TNF-α group. CONCLUSION： TNF-α, a typical factor of inflammation in the early stage of diabetic retinopathies, could cause the down-regulation of the expression of PDGF-B/PDGFR- β of endothelial cells and pericytes, which maybe a cause of the pericytes loss in the early stage of DRP.