{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T22:45:03Z","timestamp":1791326703103,"version":"4.3.1"},"reference-count":0,"publisher":"American Physiological Society","issue":"5","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["American Journal of Physiology-Cell Physiology"],"published-print":{"date-parts":[[1996,5,1]]},"abstract":"<jats:p> Trafficking, activation, and kinetics of delta F508-cystic fibrosis transmembrane conductance regulator (CFTR) and CFTR were compared in stably transduced C127I mouse mammary epithelial cells. Western blots detected a small amount of fully glycosylated delta F508-CFTR Efflux of 125I was stimulated by forskolin with the same mean effective concentration (EC50; approximately 0.5 microM) for CFTR and delta F508-CFTR cells, but the maximum response was reduced more than fivefold and its latency increased approximately threefold in delta F508-CFTR cells. In delta F508-CFTR cells, 3-isobutyl-1-methylxanthine (IBMX; EC50 = 1.45 microM) and 8-cyclopentyl-1,3-dipropylxanthine (CPX; EC50 = 58 microM) increased the peak forskolin-stimulated efflux rate approximately 2.5-fold and decreased the time to peak. A sevenfold increase in intracellular adenosine 3',5'-cyclic monophosphate (cAMP) levels accompanied potentiation of forskolin-induced 125I efflux by IBMX but not by CPX. Elevation of intracellular cAMP increased linear voltage-independent whole cell currents 30-fold in CFTR and 4-fold in delta F508-CFTR cells; the response rate in delta F508-CFTR cells was much slower. Single-channel currents were detected in 57 of 68 cell-attached patches from forskolin-prestimulated CFTR cells vs. 6 of 35 patches in delta F508-CFTR cells. Mean number of active channels per patch was 4.1 for CFTR [open probability (Po) = 0.34] and 0.2 for delta F508-CFTR (Po = 0.11). The lower Po of delta F508-CFTR resulted from an approximately threefold longer mean interburst interval. We estimate that forskolin-stimulated chloride conductance of delta F508-CFTR C127I cells is &lt; 5% of CFTR cells. CPX is approximately 25-fold more potent than IBMX in potentiating delta F508-CFTR and may operate by a mechanism other than elevation of cAMP. <\/jats:p>","DOI":"10.1152\/ajpcell.1996.270.5.c1544","type":"journal-article","created":{"date-parts":[[2017,12,24]],"date-time":"2017-12-24T19:15:36Z","timestamp":1514142936000},"page":"C1544-C1555","source":"Crossref","is-referenced-by-count":117,"title":["Delta F508-CFTR channels: kinetics, activation by forskolin, and potentiation by xanthines"],"prefix":"10.1152","volume":"270","author":[{"given":"C. M.","family":"Haws","sequence":"first","affiliation":[{"name":"Johns Hopkins University School of Medicine, Baltimore, Maryland21205, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"I. B.","family":"Nepomuceno","sequence":"additional","affiliation":[{"name":"Johns Hopkins University School of Medicine, Baltimore, Maryland21205, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M. E.","family":"Krouse","sequence":"additional","affiliation":[{"name":"Johns Hopkins University School of Medicine, Baltimore, Maryland21205, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"H.","family":"Wakelee","sequence":"additional","affiliation":[{"name":"Johns Hopkins University School of Medicine, Baltimore, Maryland21205, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"T.","family":"Law","sequence":"additional","affiliation":[{"name":"Johns Hopkins University School of Medicine, Baltimore, Maryland21205, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Y.","family":"Xia","sequence":"additional","affiliation":[{"name":"Johns Hopkins University School of Medicine, Baltimore, Maryland21205, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"H.","family":"Nguyen","sequence":"additional","affiliation":[{"name":"Johns Hopkins University School of Medicine, Baltimore, Maryland21205, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J. J.","family":"Wine","sequence":"additional","affiliation":[{"name":"Johns Hopkins University School of Medicine, Baltimore, Maryland21205, USA."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"24","container-title":["American Journal of Physiology-Cell Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/journals.physiology.org\/doi\/pdf\/10.1152\/ajpcell.1996.270.5.C1544","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,6,17]],"date-time":"2024-06-17T19:35:10Z","timestamp":1718652910000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.physiology.org\/doi\/10.1152\/ajpcell.1996.270.5.C1544"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1996,5,1]]},"references-count":0,"journal-issue":{"issue":"5","published-print":{"date-parts":[[1996,5,1]]}},"alternative-id":["10.1152\/ajpcell.1996.270.5.C1544"],"URL":"https:\/\/doi.org\/10.1152\/ajpcell.1996.270.5.c1544","relation":{},"ISSN":["0363-6143","1522-1563"],"issn-type":[{"value":"0363-6143","type":"print"},{"value":"1522-1563","type":"electronic"}],"subject":[],"published":{"date-parts":[[1996,5,1]]}}}