NITRIC-OXIDE DILATES TIGHT JUNCTIONS AND DEPLETES ATP IN CULTURED CACO-2BBE INTESTINAL EPITHELIAL MONOLAYERS
NITRIC-OXIDE DILATES TIGHT JUNCTIONS AND DEPLETES ATP IN CULTURED CACO-2BBE INTESTINAL EPITHELIAL MONOLAYERS
复制标题
DOI：
10.1152/ajpgi.1995.268.2.g361
复制
发表时间：
1995-02-01
影响因子：
4.5
通讯作者：
FINK, MP
中科院分区：
文献类型：
--
作者：
SALZMAN, AL;MENCONI, MJ;FINK, MP
我们测试了一氧化氮(NO)调节模型肠上皮(Caco-2BBe单层)紧密连接的通透性的假设。与硝普钠(SNP)孵育后，跨上皮细胞阻力呈时间和浓度依赖性降低。在1.25 mM SNP、5 mM S-亚硝基-N-乙酰青霉胺(SNAP)或1%NO孵育24 h时，细胞对荧光素磺酸的通透性增加。SNP诱导的高通透性不是由于细胞活力的丧失，正如完整的超微结构、未改变的乳酸脱氢酶释放和恢复基线通透性的能力所证实的那样。与SNP孵育可增加细胞通透性，但仅轻微增加细胞内3‘，5’-环一磷酸(CGMP)水平。与大肠杆菌耐热肠毒素孵育可显著提高cGMP水平，但对通透性的影响很小。与SNP、SNAP或气态NO孵育后，细胞内ATP水平下降。与SNP孵育后，连接肌动蛋白的荧光素-鬼臼蛋白染色减弱(共聚焦显微镜)，紧密连接变宽(电子显微镜)。我们的结论是，在培养的Caco-2BBBe细胞中，NO降低了ATP水平并可逆地增加了紧密连接的通透性。
We tested the hypothesis that nitric oxide (NO) modulates the permeability of tight junctions in a model intestinal epithelium (Caco-2BBe monolayers). Incubation with sodium nitroprusside (SNP) resulted in time- and concentration-dependent decreases in transepithelial resistance. Permeability to fluorescein sulfonic acid increased during incubation for 24 h in the presence of 1.25 mM SNP, 5 mM S-nitroso-N-acetylpenicillamine (SNAP), or 1% NO gas. SNP-induced hyperpermeability was not due to loss of cell viability, as confirmed by intact ultrastructure, unaltered lactate dehydrogenase release, and ability to recover baseline permeability. Incubation with SNP increased permeability but only minimally increased intracellular levels of guanosine 3',5'-cyclic monophosphate (cGMP). Incubation with Escherichia coli heat-stable enterotoxin greatly increased cGMP levels with only a minimal effect on permeability. Cellular ATP levels decreased after incubation with SNP, SNAP, or gaseous NO. Incubation with SNP led to diminished fluorescein-phalloidin staining of junctional actin (confocal microscopy) and widened tight junctions (electron microscopy). We conclude that NO reduces ATP levels and reversibly increases the permeability of tight junctions in cultured Caco-2BBe cells.