Soinila Jouni, Nuorva Kyösti, Soinila Seppo
Department of Oral and Maxillofacial Surgery, Central Hospital of Central Finland, 40620, Jyväskylä, Finland.
Histochem Cell Biol. 2006 Jun;125(6):717-23. doi: 10.1007/s00418-005-0123-8. Epub 2005 Dec 9.
The distribution of the three nitric oxide synthase (NOS) isoforms was determined immunohistochemically in the human minor and major salivary glands with comparison to that of rat salivary glands. In contrast to rat glands, which contained a dense plexus of neuronal NOS-immunoreactive nerve fibers, only a minority of the nerve fibers in human glands showed neuronal NOS immunoreactivity. Human labial and submandibular glands contained sparse NOS-immunoreactive fibers, while only occasional nerve fibers in the parotid or sublingual glands were stained. Furthermore, in contrast to the animal glands, most duct epithelial cells in all human salivary glands were immunoreactive for neuronal NOS. No specific immunoreactivity for inducible or endothelial NOS were observed in the nerve fibers or duct epithelium. We provide evidence to suggest that the role of nitric oxide in the regulation of salivary gland function is different in human as compared to experimental animals. Nitricergic innervation in human tissue is very sparse and thus nitric oxide is probably of minor importance as a neural regulator of salivary glands. Instead, NOS localized in duct epithelial cells suggests that nitric oxide might directly regulate saliva secretion and it is a putative source of nitrates previously reportedly secreted into the saliva.
采用免疫组织化学方法确定了三种一氧化氮合酶（NOS）同工型在人类小唾液腺和大唾液腺中的分布，并与大鼠唾液腺进行了比较。与含有密集的神经元型NOS免疫反应性神经纤维丛的大鼠腺体不同，人类腺体中只有少数神经纤维显示出神经元型NOS免疫反应性。人类唇腺和下颌下腺含有稀疏的NOS免疫反应性纤维，而腮腺或舌下腺中只有偶尔的神经纤维被染色。此外，与动物腺体不同，所有人类唾液腺中的大多数导管上皮细胞对神经元型NOS呈免疫反应性。在神经纤维或导管上皮中未观察到诱导型或内皮型NOS的特异性免疫反应性。我们提供的证据表明，与实验动物相比，一氧化氮在人类唾液腺功能调节中的作用有所不同。人类组织中的一氧化氮能神经支配非常稀疏，因此一氧化氮作为唾液腺的神经调节因子可能不太重要。相反，定位在导管上皮细胞中的NOS表明一氧化氮可能直接调节唾液分泌，并且它是先前据报道分泌到唾液中的硝酸盐的推定来源。
