Mechanical stimulation and intercellular communication increases intracellular Ca2+ in epithelial cells.
Intercellular communication of epithelial cells was examined by measuring changes in intracellular calcium concentration ([Ca2+]i). Mechanical stimulation of respiratory tract ciliated cells in culture induced a wave of increasing Ca2+ that spread, cell by cell, from the stimulated cell to neighboring cells. The communication of these Ca2+ waves between cells was restricted or blocked by halothane, an anesthetic known to uncouple cells. In the absence of extracellular Ca2+, the mechanically stimulated cell showed no change or a decrease in [Ca2+]i, whereas [Ca2+]i increased in neighboring cells. Iontophoretic injection of inositol 1,4,5-trisphosphate (IP3) evoked a communicated Ca2+ response that was similar to that produced by mechanical stimulation. These results support the hypothesis that IP3 acts as a cellular messenger that mediates communication through gap junctions between ciliated epithelial cells.
Sanderson
M J
MJ
Department of Anatomy and Cell Biology, School of Medicine, University of California, Los Angeles 90024.
Charles
A C
AC
Dirksen
E R
ER
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002450:Cell Communication / Q000187:drug effects; D002478:Cells, Cultured; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism; D006221:Halothane / Q000494:pharmacology; D015544:Inositol 1,4,5-Trisphosphate / Q000502:physiology; D007365:Intercellular Junctions / Q000378:metabolism; D008845:Microinjections; D010812:Physical Stimulation; D011817:Rabbits; D015398:Signal Transduction; D014132:Trachea / Q000166:cytology / Q000378:metabolism*
D015544:Inositol 1,4,5-Trisphosphate; D002118:Calcium; D006221:Halothane