Effect of NYD-SP27 down-regulation on ATP-induced Ca2+-dependent pancreatic duct anion secretion in cystic fibrosis cells.
Our previous study demonstrated that NYD-SP27 is a novel inhibitory PLC isoform expressed endogenously in human pancreas and upregulated in CFPAC-1 cells. The present study investigated the effect of NYD-SP27 down-regulation on the ATP-stimulated and Ca(2+)-dependent pancreatic anion secretion by CFPAC-1 cell line using short-circuit current (I(SC)) recording. NYD-SP27 antisense-transfected CFPAC-1 (AT-CF) cells exhibited a significantly higher basal transmembrane potential difference and current than those of empty vector-transfected CFPAC-1 (VT-CF) cells. Cl(-) channel blocker, DPC or Glibenclamide (1mM), and inhibitor of Na(+)-K(+)-Cl(-) cotransporter, bumetanide (100 microM) significantly inhibited the basal current in AT-CF cells. The inhibitor of adenylate cyclase, MDL12330A (20 microM), and Ca(2+)-dependent Cl(-) channel (CaCC) blocker, DIDS (100 microM) also significantly reduced the basal current in AT-CF. Apical application of ATP (10 microM) stimulated a fast transient I(SC) increase in VT-CF cells, but a more sustained rise with slower decline in AT-CF cells. Pretreatment with BAPTA-AM (50 microM) reduced the ATP-induced I(SC) response in AT-CF cells by 77.9%. PMA (1 microM), a PKC activator, inhibited the ATP-stimulated current increase (the transient peak) in VT-CF cells, but had no effect on the AT-CF cells. However, PKC inhibitor, staurosporine (40 microM) could inhibit the ATP-induced I(SC) response in AT-CF cells. The present results confirm the previously proposed inhibitory role of NYD-SP27 in the PLC pathway and demonstrate that the suppression of its expression could result in an enhancement of ATP-stimulated Ca(2+) dependent pancreatic anion secretion.
Zhu
Jin Xia
JX
Epithelial Cell Biology Research Center, Department of Physiology, Faculty of Medicine, Rm 410, Basic Medical Science Building, The Chinese University of Hong Kong, Shatin, Hong Kong, China.
Yang
Ning
N
Zhu
Hu
H
Chung
Yiu Wa
YW
Chan
Hsiao Chang
HC
D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000838:Anions; D002118:Calcium / Q000502:physiology*; D002460:Cell Line; D002462:Cell Membrane / Q000502:physiology; D003550:Cystic Fibrosis / Q000235:genetics / Q000503:physiopathology*; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics*; D010183:Pancreatic Ducts / Q000378:metabolism* / Q000503:physiopathology*; D014157:Transcription Factors / Q000235:genetics*; D014162:Transfection
D000838:Anions; D008565:Membrane Proteins; C476202:PHF7 protein, human; D014157:Transcription Factors; D000255:Adenosine Triphosphate; D002118:Calcium