Bouwens L, Klöppel G
Department of Experimental Pathology, Vrije Universiteit Brussel, Belgium.
Histochemistry. 1994 Mar;101(3):209-14. doi: 10.1007/BF00269546.
NADPH-diaphorase activity, which has been previously reported to be associated with the enzyme nitric oxide synthase (NOS), was localized cytochemically in the pancreatic islets of normal rats. All islet cells types, i.e. insulin-, glucagon-, somatostatin- and pancreatic polypeptide-immunoreactive cells, expressed NAD-PH-diaphorase histochemical activity, whereas the exocrine tissue was almost negative. In streptozotocin-treated rats, only the surviving non-beta cells in the islet periphery were stained. Isolated beta and non-beta cells also expressed intense NADPH-diaphorase activity. By electron microscopy, the enzyme was localized primarily on membranes of the endoplasmic reticulum and nuclear envelope, as previously reported for neurons. In addition the enzyme activity was found in the cis-region of the Golgi complex. These results suggest that the four types of endocrine cells of the islets of Langerhans may contain the NOS-enzyme and thus constitutively produce nitric oxide.
烟酰胺腺嘌呤二核苷酸磷酸（NADPH）黄递酶活性，先前已有报道称其与一氧化氮合酶（NOS）相关，采用细胞化学方法在正常大鼠胰岛中定位。所有胰岛细胞类型，即胰岛素、胰高血糖素、生长抑素和胰多肽免疫反应性细胞，均表达NADPH黄递酶组织化学活性，而外分泌组织几乎呈阴性。在链脲佐菌素处理的大鼠中，仅胰岛周边存活的非β细胞被染色。分离的β细胞和非β细胞也表达强烈的NADPH黄递酶活性。通过电子显微镜观察，该酶主要定位于内质网和核膜，如先前在神经元中报道的那样。此外，在高尔基复合体的顺面区域也发现了酶活性。这些结果表明，胰岛的四种内分泌细胞类型可能含有NOS酶，因此可组成性地产生一氧化氮。
