Abstract
Molecular mechanisms of intestinal chloride channel regulation and potential abnormalities in electrogenic chloride secretion in intestinal epithelium from cystic fibrosis (CF) patients were investigated by a combination of Ussing chamber, vesicle transport and off-cell patch-clamp analysis.
Short circuit current (Isc) measurements in normal and CF rectal biopsies provided evidence for i) a defect in the cAMP-provoked activation of chloride secretion and a (hyper)expression of cAMP-dependent potassium secretion in all CF patients examined (n=ll); ii) a defect in the carbachol-provoked chloride secretion and a (hyper)expression of carbachol-induced potassium secretion in 6/11 patients; iii) a residual (but still impaired) carbachol-induced chloride secretion in 5/11 CF patients (including 2 sibs). The latter class of CF patients appeared to consist genetically of compound heterozygotes for the major delta-F508 deletion, suggesting a correlation between the nature of the mutation in the CF gene and the severity of the chloride secretory defect in CF intestine.
In our search for a regulatory function of GTP-binding (G-) proteins detected previously in the luminal membrane of rat and human intestinal epithelial cells, evidence was found for the presence of a GTP[S]-activatable-and GDP[S]-inhibitable chloride conductance in the apical membrane of rat enterocytes and human colonocytes. In excised patches of human colonocyte membranes, this G-proteine-sensitive chloride conductance was identified further as a novel type of chloride channel (20pS; inwardly rectifying) that was different from the 3 3pS outwardly rectifying chloride channel activatable by cAMP-dependent proteinkinase (PK-A) and voltage depolarization. The possible role of this channel in intestinal chloride secretion and its functioning in CF intestine is under present investigation.
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References
J.H. Chen, H. Schulman and P. Gardner, 1989, A cAMP-regulated chloride channel in lymphocytes that is affected in cystic fibrosis, Science, 243:657.
H.R. de Jonge, J. Bijman and M. Sinaasappel, 1989, Relation of regulatory enzyme levels to chloride transport in intestinal epithelial cells, Ped. Pulmonology Suppl., 1:54.
H.R. de Jonge, J. Bijman and M. Sinaasappel, 1988, Ped. Pulmonology Suppl., 2:93.
R.A. Frizzell, 1987, Cystic Fibrosis: A disease of ion channels Trends in Neurosci., 10:190.
M. Li, J.D. McCann, C.M. Liedtke, A.C. Nairn, P. Greengard, M.J. Welsh, Cyclic AMP-dependent protein kinase opens chloride channels in normal but not cystic fibrosis airway epithelium, 1988, Nature, 331:358.
P.M. Quinton and J. Bijman, 1983, Higher bioelectric potentials due to decreased chloride absorption in the sweat glands of patients with cystic fibrosis, New Engl. J. Med., 308:185.
P.M. Quinton, 1983, Chloride impermeability in cystic fibrosis, Nature, 301:421.
J.R. Riordan, J.M. Rommens, B.-S. Kerem, N. Alon, R. Roz-mahel, Z. Grzelczak, J. Zielenski, S. Lok, N., Plavsic, J.-L. Chou, M.L. Drumm, M.C. Iannuzzi, F.S. Collins and L.-C. Tsui, 1989, Identification of the CF gene: cloning and characterization of complementary DNA, Science, 245:1066.
R.L. Shoemaker, R.A. Frizzell, T.M. Dwyer and J.M. Farley, 1986, Single-channel currents from canine tracheal epithelial cells, Biochem. Biophys. Acta, 858:235.
M.J. Welsh and C.M. Liedtke, 1986, Chloride and potassium channels in cystic fibrosis epithelia, Nature, 322:467.
H.R. de Je Jonge, N. van den Berghe, B.C. Tilly, M. Kansen and J. Bijman, 1989, (Dys)regulation of epithelial chloride channels, J. Biochem. soc. Trans., 17:816.
J.L. Goldstein, N.T. Nash, F. Al-Bazzaz, T.J. Layden, M.C. Rao, 1988, Rectum has abnormal ion transport but normal cAMP-binding proteins in cystic fibrosis, Am. J. Physiol., 254:C719.
A. Yatani, J. Codina, A.M. Brown and L. Birnbaumer, 1987, A G protein directly regulates mammalian cardiac calcium channels, Science, 238:1288.
A. Yatani, J. Codina, A.M. Brown and L. Birnbaumer, 1987, Direct activation of mammalian atrial muscarinic potassium channels by GTP regulatory protein Gk, Science, 235:442.
M. Mohrmann, H.F. Cantiello and D.A. Ausiello, 1987, Inhibition of epithelial Na+ transport by atriopeptin, protein kinase C and pertussis toxin, Am. J. Physiol., 253:F372.
D.B. Light, D.A. Ausiello and B.A. Stanton, 1989, J. Clin. Invest., 84:352.
B.C. Tilly, M. Kansen, P.G.M. van Gageldonk, N. van den Berghe, J. Bijman, H.R. de Jonge, 1990, Activation of intestinal chloride channels by GTP-binding regulatory proteins, submitted.
N.P. Illsey and A.S. Verkman, 1987, Membrane chloride transport measured using a chloride-sensitive fluorescent probe, Biochemistry, 26:1215.
J.R. Demarest, D.D.F. Loo and G. Sachs, 1989, Activation of apical chloride channels in the gastric oxyntic cell, Science, 245:402.
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Bijman, J. et al. (1991). Chloride Transport in the Cystic Fibrosis Enterocyte. In: Tsui, LC., Romeo, G., Greger, R., Gorini, S. (eds) The Identification of the CF (Cystic Fibrosis) Gene. Advances in Experimental Medicine and Biology, vol 290. Springer, Boston, MA. https://doi.org/10.1007/978-1-4684-5934-0_27
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DOI: https://doi.org/10.1007/978-1-4684-5934-0_27
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