Proliferation mechanisms of endothelial cells through crosstalk between endothelial cells and vascular smooth cells

背景：在动物植入模型中，注射前列腺素E_1脂微球可显著促进移植静脉内皮化，血管内皮细胞与内皮细胞共培养可促进内皮细胞的增殖。然而，在共培养模型中，PGE1并不一定促进内皮细胞的增殖，而在共培养模型中，内皮细胞的增殖也不一定受到PGE1的促进。目的：探讨PGE1是否能阻止血管内皮细胞的死亡。方法：从犬颈静脉取内皮细胞和血管内皮细胞，将其接种于跨滤膜孔内。当内皮细胞融合时，用50 ng/mlPGE1与SMC共同培养。用Annexin V和Hoechst 33342分别用增殖法和荧光法检测内皮细胞的存活率和凋亡率。结果：PGE1组和对照组内皮细胞存活率分别为92.1%和76.0%，1.2%和4.7%(P<0.01)。培养第5天的内皮细胞凋亡率分别为2.1%和5.1%，第7天的凋亡率分别为1.2%和4.7%(P&lt；0.01)。结论：前列腺素E_1可抑制内皮细胞的凋亡，从而提高内皮细胞的存活率。

Background: In an animal implantation model, lipo PGE1 administration brought a significant enhancement of Vein graft reendothelialization, and ECs proliferation was enhanced by coculture wth VSMCs. However, the ECs prohferation was not necessarily enhanced by PGE1 in coculture model, whereas endothelial cells (ECs) proliferation was not enhanced by PGE1 in coculture model Our previous study demonstrated ECs proliferation was enhanced by coculture with VSMCs.Objectives: We investigated whether PGE1 prevented apoptotic ECs death.Methods: ECs and VSMCs were harvested from the canine jugular vein, the ECs were cultured in the lower well of a transfilter coculture system, while SMCs were seeded on a transfilter well. When the ECs became confluent, the ECs cultured with the SMCs with daily administration of 50 ng/ml PGE1. Survival rate and apoptosis rate of ECs were measured by a proliferation assay and a fluolescence method with annexin V and Hoechst 33342. The results were compared between the PGE1 group and Control groups (without PGE1 administration) at day 5 and day 7.Result: Survival rate of ECs in the PGEl group and Control group were 92.1 % and 76.0 % at day 1.2 % and 4.7 % at day 7 (P<0.01). Apoptosis rate of ECs were 2,1% and 5.1 % at day 5, and 1.2 % and 4.7 % at day 7, respectively (P<0.01).Conclusion: The present results suggested that PGE1 inhibits apoptotic ECs death, resulting in improvement of ECs Survival rate.