Glucose-dependent insulinotropic peptide (GIP) gene expression in the rat salivary gland.
Glucose-dependent insulinotropic peptide (GIP) gene expression in the rat salivary gland.
复制标题
大鼠唾液腺中葡萄糖依赖性促胰岛素肽（GIP）基因的表达。
DOI：
10.1016/0303-7207(95)03665-t
复制
发表时间：
1995
影响因子：
4.1
通讯作者：
Wolfe,MM
中科院分区：
文献类型：
--
作者：
Tseng,CC;Boylan,MO;Jarboe,LA;Williams,EK;Sunday,ME;Wolfe,MM
先前的研究表明，在营养摄入后，GIP主要从上小肠释放。除了存在于大鼠小肠中，GIP转录本也被定位于下颌唾液腺（SSG）。目前的研究旨在进一步表征GIP基因在SSG中的表达。在妊娠第18天和第20天处死怀孕大鼠，然后取出大鼠胎儿。然后在1、3、7、10、14和21日龄时从胎儿和新生幼犬身上切除十二指肠、胰腺和SSG。采用特异性大鼠GIP探针提取RNA并进行Northern blot分析。GIP转录本在胎儿18天时首次在十二指肠中检测到，并在出生时达到最高水平。相比之下，直到出生后10天才在SSG中观察到GIP mRNA，在胎儿或新生儿胰腺中均未检测到。使用35s标记的反义GIP RNA探针对SSG进行原位杂交，发现GIP基因的表达仅限于导管细胞，而在腺泡中没有转录本。在单独的实验中，禁食过夜的大鼠被给予水或10%的葡萄糖。虽然水喂养大鼠在口服葡萄糖摄入后没有检测到变化，但在60和240分钟时检测到SSG - GIP基因表达小幅但显著增加。这些初步研究的结果表明，通过Northern分析和原位杂交，以及葡萄糖餐后SSG中GIP mRNA的表达增加，GIP可能在大鼠唾液腺中发挥功能作用。
Previous studies have indicated that following nutrient ingestion, GIP is released principally from the upper small intestine. In addition to its presence in the rat small intestine, GIP transcripts have also been localized to the submandibular salivary gland (SSG). The present studies were directed to further characterize expression of the GIP gene in the SSG. Pregnant rats were sacrificed at gestational days 18 and 20, followed by the removal of rat fetuses. The duodenum pancreas, and SSG were then excised from the fetuses, as well as from neonatal pups at ages 1, 3, 7, 10, 14, and 21 days. RNA was extracted and measured by Northern blot analysis using specific rat GIP probes. GIP transcripts were first detected in the duodenum in the 18-day fetus and reached maximum levels at birth. In contrast, GIP mRNA was not observed in the SSG until 10 days postnatally and was not detected at all in either the fetal or neonatal pancreas. In situ hybridization of the SSG using an35S-labelled antisense GIP RNA probe demonstrated expression of the GIP gene to be limited to ductal cells, with no transcripts present in acini. In separate experiments, rats fasted overnight were given water or 10% glucose. While no changes were detected in water-fed rats following oral glucose ingestion, small, but significant increases in SSG GIP gene expression were detected at 60 and 240 min. The results of these initial studies suggest the possibility of a functional role for GIP in the rat salivary gland by the demonstration of GIP mRNA in the SSG by Northern analysis and in situ hybridization, as well as by an increase in SSG GIP gene expression following a glucose meal.