Expression and localization of vascular endothelial growth factor in the endocrine system

血管内皮生长因子（VIEGE）是一种有效的血管生成丝裂原，也能增加血管通透性。使用特异性抗体在光镜和电镜下研究了VEGF在健康成年大鼠全身的免疫组织化学定位。在某些内分泌细胞类型中，即甲状腺滤泡旁细胞、内分泌胰腺B细胞、肾上腺髓质N细胞和少数垂体前叶TSH细胞中检测到对VEGF的强烈至中度免疫反应。在超微结构水平上，VEGF免疫反应性仅局限于所有免疫阳性内分泌细胞的分泌颗粒中。这些结果为正常成年大鼠内分泌细胞亚群中VIEGF的存在提供了免疫组化证据，提示这些分泌细胞通过VEGF的旁分泌作用调节局部血管通透性（文献1）。在呼吸道上皮、小肠固有层和大肠上皮中均可见较强的单细胞VEGF。通过其大细胞质颗粒的超微结构特征，这些vegf阳性细胞被鉴定为球状白细胞（GL），也称为粘膜肥大细胞（MMC）。免疫反应性仅局限于GIIMMC的细胞质颗粒。在连续切片检查时，呼吸道和消化道的GL/MMC对抗组胺抗体仅表现出弱反应性。相比之下，位于消化道粘膜下层、呼吸道结缔组织和其他各种器官的结缔组织肥大细胞（CTMC）对组胺呈强烈免疫阳性，而对VBGF无反应性。VEGF免疫反应性在GL/MMC中特异出现，提示该细胞类型参与近5y微血管通透性的旁分泌调节，VEGF可作为区分GL/MMC与CTMC的组织化学标志物（文献2）。少

Vascular endothelial growth factor (VIEGE) is a potent angiogenic mitogen and also increases vascular permeability. Immunohistochemical localization of VEGF in the entire body of healthy adult rats was investigated at light and electron microscopic levels using a specific antibody. Intense to moderate immunoreactivities for VEGF were detected in certain endocrine cell types, namely, the parafollicular cell of thyroid gland, B cell of endocrine pancreas, N cell of adrenal medulla and a minority of the TSH cell of anterior pituitary gland. At the ultrastructural level, VEGF immunoreactivity was localized exclusively in the secretory granules of all immunopositive endocrine ells. These results provided immunohistochemical evidence for the occurrence of VIEGF in subsets of endocrine cells of normal adult rats, suggesting that these secretory cells regulate local vascular permeability through a paracrine action of VEGF (Reference 1).The results also showed solitary cells with strong VEGF im … More munoreactivity scattered in the epithelium of the respiratory tract as well as in the lamina propria and epithelium of the small and large intestines. By ultrastructural features of their large cytoplasmic granules, these VEGF-positive cells were identified as globule leukocytes (GL), also called mucosal mast cells (MMC). The immunoreactivity was localized exclusively in the cytoplasmic granules of GIIMMC.When examined in serial sections, GL/MMC in the respiratory and digestive tracts showed only weak reactivity to anti-histamine antibody. In contrast, connective tissue mast cells (CTMC), which were located in the submucosa of digestive tract and in the connective tissue of respitratory tract and a variety of other organs, were intensely immunopositive for histamine, whereas they showed no reactivity for VBGF.The specific appearance of VEGF immunoreactivity in GL/MMC suggested that this cell type is involved in the paracrine regulation of the permeability of nearl5y microvessels, and that VEGE can be used as a histochemical marker to distinguish GL/MMC from CTMC(Reference2). Less