ACELL September 46/3
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چکیده
Stevens, Randel J., Jeffery S. Weinert, and Nelson G. Publicover. Visualization of origins and propagation of excitation in canine gastric smooth muscle. Am. J. Physiol. 277 (Cell Physiol. 46): C448–C460, 1999.—The origin and spread of excitation were visualized with fluo 3 fluorescence in tissues isolated from canine gastric antrum. Sheets of circular muscle (5 3 6 mm) had at least 1 (30%) and up to 3 discrete slow-wave pacing sites located near the longitudinalcircular muscle boundary, whereas similarly sized longitudinal sheets had an average of 5 sites (range 3–12 sites) that initiated Ca21 waves. Superimposed fluorescent oscillations (circular muscle) and spikes (longitudinal muscle) were seen to initiate and propagate as distinct events, separate from their underlying activities. Average propagation velocities transverse (6–7 mm/s) and parallel (39–45 mm/s) to the long axis of muscle fibers were similar for each type of event in circular and longitudinal tissues; however, distinct regions where velocities of some (but not all) events decreased by up to an order of magnitude were present. The distance propagated by individual events was limited by collisions with concurrent excitable events or recently activated regions. Complex patterns of excitation in gastrointestinal smooth muscle arise as a result of interactions between multiple pacing sites, heterogeneous conduction velocities, and the interplay of adjacent pacemaker domains.
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ACELL September 46/3
Dodd, J. S., J. A. Raleigh, and T. S. Gross. Osteocyte hypoxia: a novel mechanotransduction pathway. Am. J. Physiol. 277 (Cell Physiol. 46): C598–C602, 1999.—Bone is a unique tissue in which to examine mechanotransduction due to its essential role in weight bearing. Within bone, the osteocyte is an ideal cellular mechanotransducer candidate. Because osteocytes reside distant from the blood supp...
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Zeiske, Wolfgang, Ilse Smets, Marcel Ameloot, Paul Steels, and Willy Van Driessche. Intracellular pH shifts in cultured kidney (A6) cells: effects on apical Na1 transport. Am. J. Physiol. 277 (Cell Physiol. 46): C469–C479, 1999.—We report, for the epithelial Na1 channel (ENaC) in A6 cells, the modulation by cell pH (pHc) of the transepithelial Na1 current (INa), the current through the individu...
متن کاملACELL September 46/3
Shepard, Allan R., and James L. Rae. Electrically silent potassium channel subunits from human lens epithelium. Am. J. Physiol. 277 (Cell Physiol. 46): C412–C424, 1999.—We describe the cloning and characterization of the first human members, hKv9.1 and hKv9.3, of the electrically silent delayed-rectifying-like K1 channel subfamily. Their modulatory effects on the electrically active subfamily m...
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JOHN M. PARK,1 ROSALYN M. ADAM,1 CRAIG A. PETERS,1 PAUL D. GUTHRIE,1 ZIJIE SUN,2 MICHAEL KLAGSBRUN,3 AND MICHAEL R. FREEMAN3 1Urologic Laboratory, Department of Urology, 3Laboratory for Surgical Research, Children’s Hospital, and Department of Surgery, Harvard Medical School, Boston, Massachusetts 02115; and 2Departments of Surgery and Genetics, Stanford University School of Medicine, Stanford,...
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