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PubMed · 16231703

[Regulatory volume decrease and its mechanism in nasopharyngeal epithelial cells].

Xue Rong Sun·Li Xin Chen·Jian Wen Mao·Lin Yan Zhu·Si Huai Nie·Ping Zhong·Pan Li·Li Wei Wang
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Abstract

To investigate regulatory volume decrease (RVD) and its mechanism in primary-culturing fetal human nasopharyngeal epithelial cells, living cell imaging technique was employed to detect the volume changes following exposure to hypotonic solution, and blockage of Cl- channels was used to clarify the role of Cl- channels in RVD. The results showed that extracellular hypotonic treatment swelled the cells and induced RVD. 47% hypotonic solution (160 mOsmol/L) swelled the cell by 144.7% and induced 38.7% recovery of cell volume within 20 min. RVD was correlated negatively to the extracellular osmolarity (r=-0.99, P<0.05) and positively to the swelling volume(r=0.99, P<0.05) in "S" shape, respectively. Chloride channel blockers, tamoxfen (20 micromol/ L), ATP (10 mmol/L) and NPPB (100 micromol/L), inhibited RVD by 100%, 76.3% and 62.7% (P< 0.01), respectively. The results indicated that primary-culturing fetal human nasopharyngeal epithelial cells are capable of RVD. Cl- efflux through Cl- channels is the key mechanism of RVD.

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Adenosine TriphosphateCell SizeCells, CulturedChloride ChannelsEpithelial CellsHumansHypotonic SolutionsNasopharynxNitrobenzoatesTamoxifenEnglish AbstractJournal ArticleResearch Support, Non-U.S. Gov't

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Xue Rong Sun, Li Xin Chen, Jian Wen Mao, Lin Yan Zhu, Si Huai Nie, Ping Zhong, Pan Li, Li Wei Wang. 2005. [Regulatory volume decrease and its mechanism in nasopharyngeal epithelial cells].. https://pubmed.ncbi.nlm.nih.gov/16231703/

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