Role of phospholipases in the proliferation or the migration of human smooth muscle cells

• Main Authors: Wei-Huan Chu, 朱偉寰
• Other Authors: Ming-Te Lin
• Format: Others
• Language: zh-TW
• Published: 1995
• Online Access: http://ndltd.ncl.edu.tw/handle/18951263591870584165

碩士 === 國立成功大學 === 生物化學研究所 === 83 === Key events in the pathological narrowing of the lumen at the site of an arterial plague are the migration and proliferation of human smooth muscle cells which can be stimulated by growth factor ,such as PDGF and bFGF.Recent evidances have suggested phospholipases are activated in growth factor-induced cells. Therefore,experiment were designed to study whether the activation of phospholipases involve in the proliferation or the migration of human smooth muscle cells. Human umbilical vein smooth muscle cells were isolated from human umbilical vein by explant culture.Cells between 5 to 10 passages were used in this study.Mitogenic and chemotactic responses were measured by 3H-thymidine incorporation and boyden's chambers respectively. Lipids of extracts were separated and analyzed by thin layer chromatography, and quantitated by liquid scintillation counter. Our results showed that PDGF-BB stimulated the proliferation and migration of HUVSMCs, and PDGF AA stimulated the proliferation only. At the same time,PDGF-BB increased fromation of DAG activated PLD and PLA2. PDGF-AA increased formation of DAG only.When cells were treated with fMLP, a chemotactic agent for smooth muscle cells,activities of PLD and PLA2 were also increased .These results suggest that the activation of PLD and PLA2 is involved in migration while the formation of DAG may be related to proliferation. A further analysis on the effect of phosphatidic acid on the proliferation and migration of HUVSMCs revealed that PA could stimulate the proliferation and the migration of HUVSMCs. Additionally in the presence of propranolol, a PA phosphohydrolase inhibitor,PA stimulated migration only, suggesting that PA itself may stimulate the migration while its metabolite, DAG,may be involved in proliferation.