Bacic M, Edwards N A, Merrill M J
Surgical Neurology Branch, National Institute for Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA.
Growth Factors. 1995;12(1):11-5. doi: 10.3109/08977199509003209.
Vascular endothelial growth factor (VEGF)/vascular permeability factor (VPF), exists as multiple forms due to alternative splicing of mRNA. VEGF165/164 (human/rodent homologue) is often assumed to be the predominant form, although truly quantitative assessments are lacking. We have used the RNase protection assay to directly quantitate the relative abundance of VEGF mRNA forms in five rat tissues (brain, kidney, lung, spleen, and heart) and two rat glioma cell lines (C6 and 9L). The three major forms, which code for proteins of 188, 164, and 120 amino acids, were observed in all of the tissues and cells examined. However, the relative abundance differed among the samples. VEGF188 was the predominant form (> 50% of total VEGF mRNA) in heart and lung, but was the least abundant form (6-15%) in all other samples. VEGF164 was lower (approximately 25%) in heart and lung, but was predominant (> 50%) in brain and kidney. VEGF164 and VEGF120 were present in equimolar amounts (each form approximately 46% of total) in the spleen, C6, and 9L. VEGF120 was also present in kidney (38%) and lung (27%) and was least abundant (approximately 15%) in brain and heart. A rat homologue of VEGF206 was not observed. VEGF mRNA splicing occurs in a tissue-specific manner. The assumption that the predominant physiologic form of VEGF is a VEGF165/164 homodimer should be viewed with caution.
血管内皮生长因子（VEGF）/血管通透因子（VPF）因mRNA的可变剪接而以多种形式存在。尽管缺乏真正的定量评估，但VEGF165/164（人/啮齿动物同源物）通常被认为是主要形式。我们使用核糖核酸酶保护分析法直接定量测定了五种大鼠组织（脑、肾、肺、脾和心脏）和两种大鼠胶质瘤细胞系（C6和9L）中VEGF mRNA各形式的相对丰度。在所有检测的组织和细胞中均观察到了编码188、164和120个氨基酸的三种主要形式。然而，各样本中的相对丰度有所不同。VEGF188是心脏和肺中的主要形式（占总VEGF mRNA的>50%），但在所有其他样本中是含量最少的形式（6-15%）。VEGF164在心脏和肺中的含量较低（约25%），但在脑和肾中占主导地位（>50%）。VEGF164和VEGF120在脾脏、C6和9L中以等摩尔量存在（每种形式约占总量的46%）。VEGF120在肾（38%）和肺（27%）中也有存在，在脑和心脏中含量最少（约15%）。未观察到VEGF206的大鼠同源物。VEGF mRNA剪接以组织特异性方式发生。应谨慎看待VEGF的主要生理形式是VEGF165/164同二聚体这一假设。
