Gresz V, Burghardt B, Ferguson C J, Hurley P T, Takács M, Nielsen S, Varga G, Zelles T, Case R M, Steward M C
Dept. of Oral Biology, semmelweis University of Medicine, Budapest, Hungary.
Arch Oral Biol. 1999 May;44 Suppl 1:S53-7.
Aquaporin (AQP) water channels are widely expressed in the membranes of fluid-transporting epithelia. Despite the fact that salivary glands are the site of considerable water movement, relatively little is known about the role of aquaporins in human salivary glands. We have examined the expression of AQP1 in human parotid, sublingual and labial salivary glands. Total RNA was extracted from glandular tissue obtained from surgery or biopsy. The presence of AQP1 mRNA was demonstrated in each of the three glands by RT-PCR using primers specifically designed for human AQP1. The PCR product from the labial gland RNA was further amplified with nested primers and the sequence confirmed by automated fluorescent DNA sequencing. The cleaned first PCR product from these glands was then used as a 32P-labelled hybridization probe in a Northern analysis which confirmed the presence of significant amounts of AQP1 transcript in all three glands. AQP1 expression was also demonstrated in cryosections of human labial glands by immunohistochemistry using peroxidase-linked antibodies. Antibody labelling was most prominent in the capillaries but was also evident in the basal regions of the labial gland acini, and may therefore be associated with the serous demilunes which are believed to be a significant site of fluid movement.
水通道蛋白（AQP）水通道广泛表达于液体转运上皮细胞的膜中。尽管唾液腺是大量水分移动的场所，但关于水通道蛋白在人类唾液腺中的作用却知之甚少。我们研究了水通道蛋白1（AQP1）在人类腮腺、舌下腺和唇腺中的表达。从手术或活检获取的腺组织中提取总RNA。使用专门为人AQP1设计的引物，通过逆转录聚合酶链反应（RT-PCR）在这三种腺体中均证实了AQP1 mRNA的存在。来自唇腺RNA的PCR产物用巢式引物进一步扩增，并通过自动荧光DNA测序确认序列。然后将这些腺体纯化的首次PCR产物用作32P标记的杂交探针进行Northern分析，证实所有三种腺体中均存在大量的AQP1转录本。通过使用过氧化物酶连接抗体的免疫组织化学方法，在人类唇腺的冰冻切片中也证实了AQP1的表达。抗体标记在毛细血管中最为显著，但在唇腺腺泡的基部区域也很明显，因此可能与浆液半月有关，而浆液半月被认为是液体移动的重要部位。
