VEGF activates receptor-operated cation channels in human microvascular endothelial cells
VEGF activates receptor-operated cation channels in human microvascular endothelial cells
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DOI：
10.1161/01.atv.0000231518.86795.0f
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发表时间：
2006-08-01
影响因子：
8.7
通讯作者：
Bates, D. O.
中科院分区：
文献类型：
--
作者：
Cheng, H. -W.;James, A. F.;Bates, D. O.
血管内皮生长因子（VEGF）通过刺激内皮细胞钙离子内流发挥其多种作用，但对介导VEGF诱导的阳离子内流的通道知之甚少。本研究的目的是首次测量和表征人微血管内皮细胞（HMVECs）中VEGF激活的阳离子电流。方法和结果-对HMVECs进行全细胞膜片钳记录。在施加的电压斜坡，VEGF激活的电流在0 mV逆转，是敏感的钆，并需要细胞外阳离子。噪声分析得到27 pS的单通道电导。该电流不依赖于细胞内钙储备，并且不被三磷酸肌醇（IP 3）受体或丝氨酸/苏氨酸激酶抑制剂阻断，但被氟芬那酸部分抑制。类似的电流被1-油酰基-2-乙酰基-sn-甘油（OAG）激活，OAG是甘油二酯（DAG）的膜渗透类似物。为了确定VEGF是否可以激活具有类似特性的重组离子通道，我们研究了VEGF对VEGFR 2和经典瞬时受体电位（TRPC）通道TRPC 3或TRPC 6共转染的中国仓鼠卵巢细胞的影响。VEGF诱导类似的电流，上述在VEGFR 2-TRPC 3和VEGFR 2-TRPC 6细胞，但不是在细胞转染任一cDNAsolid.Conclusions-VEGF激活受体操作的阳离子电流在HMVECs和OAG可以直接激活类似的电流在这些细胞。VEGF还能够通过VEGFR 2激活异源表达的TRPC 3/6通道。
Objective-Vascular endothelial growth factor (VEGF) exerts many of its effects by stimulating endothelial calcium influx, but little is known about channels mediating VEGF-induced cation entry. The aim of this study was to measure and characterize for the first time the VEGF-activated cation current in human microvascular endothelial cells (HMVECs).Methods and Results-Whole-cell patch-clamp recordings were made from HMVECs. During applied voltage ramps, VEGF activated a current that reversed at 0 mV, was sensitive to gadolinium, and required extracellular cations. Noise analysis yielded a single-channel conductance of 27 pS. The current was not dependent on intracellular calcium stores, and was not blocked by inositol triphosphate (IP3) receptor or serine/threonine kinase inhibition but was partially inhibited by flufenamic acid. A similar current was activated by 1-oleoyl-2-acetyl-sn-glycerol (OAG), a membrane-permeant analog of diacylglycerol (DAG). To determine whether VEGF could activate recombinant ion channels with similar properties, we investigated the effect of VEGF on Chinese hamster ovary cells cotransfected with VEGFR2 and the canonical transient receptor potential (TRPC) channels, TRPC3 or TRPC6. VEGF induced a similar current to that described above in VEGFR2-TRPC3 and VEGFR2-TRPC6 cells but not in cells transfected with either cDNA alone.Conclusions-VEGF activates a receptor-operated cation current in HMVECs and OAG can activate directly a similar current in these cells. VEGF is also able to activate heterologously expressed TRPC3/6 channels through VEGFR2.