{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,6]],"date-time":"2026-02-06T00:49:32Z","timestamp":1770338972485,"version":"3.49.0"},"reference-count":0,"publisher":"American Physiological Society","issue":"4","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["American Journal of Physiology-Cell Physiology"],"published-print":{"date-parts":[[1991,4,1]]},"abstract":"<jats:p> We used the secretory colonic cell line T84 to study the regulatory pathways controlling the Ca-stimulated Cl conductance [GCl(Ca)]. Under whole cell patch clamp, basal (unstimulated) current levels averaged 73 +\/- 9 pA\/20 pF (n = 93) and increased to 600 +\/- 100 pA\/20 pF (n = 53; at +100 mV) on exposure to 1-2 microM ionomycin. Bath application of the calmodulin (CaM) antagonists trifluoperazine, calmidazolium, or sphingosine (50 microM) reversibly inhibited GCl(Ca), whereas the protein kinase C antagonists H7 and phloretin (50 microM) were without effect. This suggests that increases in intracellular Ca stimulate GCl(Ca) via a CaM-dependent process rather than activating Cl channels directly. To assess the involvement of protein kinases in the Ca-dependent stimulation of Cl conductance, we employed pseudosubstrate peptide inhibitors of protein kinase C (PKC) and the Ca\/CaM-dependent protein kinase II (CaMKII). Cellular concentrations of inhibitors during whole cell recording were estimated to be 4-20 times the inhibitory constant values for kinase inhibition observed in vitro. Pipette solutions containing the PKC peptide inhibitor PKC-(19-36) (7.5 microM) had no effect on GCl(Ca). In contrast, stimulation of GCl(Ca) by ionomycin was abolished when pipette solutions contained 10 microM CaMKII peptide inhibitor CaMKII-(273-302). The truncated peptide CaMKII-(284-302) (20 microM) lacks the CaMKII inhibitory domain and did not affect GCl(Ca). These data suggest that CaM, acting through the multifunctional CaMKII, mediates the Ca-dependent stimulation of Cl conductance in colonic secretory cells. <\/jats:p>","DOI":"10.1152\/ajpcell.1991.260.4.c877","type":"journal-article","created":{"date-parts":[[2017,12,24]],"date-time":"2017-12-24T12:46:40Z","timestamp":1514119600000},"page":"C877-C882","source":"Crossref","is-referenced-by-count":116,"title":["CaMKII mediates stimulation of chloride conductance by calcium in T84 cells"],"prefix":"10.1152","volume":"260","author":[{"given":"R. T.","family":"Worrell","sequence":"first","affiliation":[{"name":"Department of Physiology and Biophysics, University of Alabama, Birmingham 35294."}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"R. A.","family":"Frizzell","sequence":"additional","affiliation":[{"name":"Department of Physiology and Biophysics, University of Alabama, Birmingham 35294."}],"role":[{"role":"author","vocabulary":"crossref"}]}],"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.1991.260.4.C877","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,6,17]],"date-time":"2024-06-17T19:46:03Z","timestamp":1718653563000},"score":1,"resource":{"primary":{"URL":"https:\/\/journals.physiology.org\/doi\/10.1152\/ajpcell.1991.260.4.C877"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1991,4,1]]},"references-count":0,"journal-issue":{"issue":"4","published-print":{"date-parts":[[1991,4,1]]}},"alternative-id":["10.1152\/ajpcell.1991.260.4.C877"],"URL":"https:\/\/doi.org\/10.1152\/ajpcell.1991.260.4.c877","relation":{},"ISSN":["0363-6143","1522-1563"],"issn-type":[{"value":"0363-6143","type":"print"},{"value":"1522-1563","type":"electronic"}],"subject":[],"published":{"date-parts":[[1991,4,1]]}}}