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

血管内皮生长因子(VIEGE)是一种强大的血管生成有丝分裂原，也能增加血管通透性。用一种特异性抗体对健康成年大鼠全身血管内皮生长因子的免疫组织化学定位进行了光镜和电子显微镜研究。在甲状腺滤泡旁细胞、内分泌B细胞、肾上腺髓质N细胞和少数垂体前叶TSH细胞中可检测到较强至中等强度的VEGF免疫反应。在超微结构水平上，所有免疫阳性的内分泌细胞中，VEGF免疫反应仅定位于分泌颗粒。这些结果为正常成年大鼠的内分泌细胞亚群中存在血管内皮细胞生长因子提供了免疫组织化学证据，提示这些分泌细胞通过血管内皮生长因子的旁分泌作用来调节局部血管通透性(参考文献1)。此外，结果还显示孤立细胞在…中有很强的血管内皮生长因子更多的免疫反应散布在呼吸道上皮以及小肠和大肠的固有层和上皮中。根据其大的胞浆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)，也被称为粘膜肥大细胞(MMC)。免疫反应仅定位于GIIMMC的胞浆颗粒。连续切片检查，呼吸道和消化道的GL/MMC仅对抗组胺抗体呈弱反应。结缔组织肥大细胞(CTMC)位于消化道粘膜下层、呼吸道结缔组织和多种器官中，对组胺呈强阳性反应，而对VBGF呈阴性反应。GL/MMC中VEGF免疫反应阳性的特异性表现提示，该细胞参与了近15年微血管通透性的旁分泌调节，血管内皮可作为区别GL/MMC和CTMC的组织化学标志(参考文献2)。较少

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