Lamberts R, Stumps D, Plümpe L, Creutzfeldt W
Department of Internal Medicine, Georg-August-University of Göttingen, Federal Republic of Germany.
Histochemistry. 1991;95(4):373-82. doi: 10.1007/BF00266965.
In the gastrointestinal tract somatostatin is localized in endocrine cells and in neurons. The antral somatostatin (D-) cell shares features of both cell types. The activity of the antral D-cell is regulated by intragastric pH. Therefore different states of gastric acidity were induced experimentally in order to study D-cell morphology at the electron microscopical level. The morphological findings were related to measurements of plasma and tissue concentrations of the peptide. The D-cell is characterized by extensive membrane interdigitations with neighbouring cells. Changes in the activity of antral D-cells are reflected by an increase in cytoplasmic secretory granule density and a shift of secretory granules towards basal cell processes. Direct endocrine cell contacts at the level of the perikarya were rarely observed. The intracellular distribution of secretory granules suggests that cell communication is more likely to take place at the level of the strongly immunoreactive cytoplasmic processes. No evidence for endocrine or exocrine (luminar) secretion was observed morphologically. This is in agreement with the concept of paracrine secretion of the antral D-cell.
在胃肠道中，生长抑素定位于内分泌细胞和神经元中。胃窦部的生长抑素（D-）细胞兼具这两种细胞类型的特征。胃窦部D细胞的活性受胃内pH值调节。因此，通过实验诱导出不同的胃酸状态，以便在电子显微镜水平上研究D细胞的形态。形态学研究结果与肽的血浆和组织浓度测量结果相关。D细胞的特征是与相邻细胞有广泛的膜指状交叉。胃窦部D细胞活性的变化表现为细胞质分泌颗粒密度增加以及分泌颗粒向基底细胞突起移动。在核周水平很少观察到内分泌细胞之间的直接接触。分泌颗粒的细胞内分布表明，细胞间通讯更可能发生在强免疫反应性细胞质突起水平。在形态学上未观察到内分泌或外分泌（腔内分泌）的证据。这与胃窦部D细胞旁分泌的概念相符。
