Ishida N, Maruo J, Mita S
Discovery Research Division, Santen Pharmaceutical Co., Ltd., Nara, Japan.
Biochem Biophys Res Commun. 1996 Jul 5;224(1):1-4. doi: 10.1006/bbrc.1996.0974.
Lacrimal glands transport fluid for secretion as tears. To examine whether the expression of the aquaporin family of water channels is essential for water transport in lacrimal glands, we determined the water permeability in Xenopus oocytes injected with rat lacrimal gland poly(A)+ RNA. In oocytes injected with poly(A)+ RNA, osmotic water permeability was 4-fold higher than that observed in vehicle-injected controls. The enhanced water permeability was inhibited by 65% by coinjection of poly(A)+ RNA with antisense aquaporin-5 but not antisense aquaporin-1 oligonucleotide. To detect aquaporin mRNA in rat lacrimal glands, we performed reverse transcription-polymerase chain reaction analysis. PCR products were detected using specific aquaporin-5 primers. Our results strongly suggest that rat lacrimal glands express aquaporin-5 water channels for lacrimation.
泪腺将液体运输并分泌为眼泪。为了研究水通道蛋白家族的表达对于泪腺中的水运输是否至关重要，我们测定了注射大鼠泪腺聚腺苷酸加尾RNA（poly(A)+ RNA）的非洲爪蟾卵母细胞的水渗透性。在注射了poly(A)+ RNA的卵母细胞中，渗透水渗透性比注射溶剂的对照组高4倍。通过将poly(A)+ RNA与水通道蛋白-5反义寡核苷酸共注射，增强的水渗透性被抑制了65%，但与水通道蛋白-1反义寡核苷酸共注射则没有这种效果。为了检测大鼠泪腺中的水通道蛋白mRNA，我们进行了逆转录-聚合酶链反应分析。使用特异性水通道蛋白-5引物检测到了PCR产物。我们的结果强烈表明，大鼠泪腺表达水通道蛋白-5水通道用于流泪。
