Ca2+ flux as an initial event in phagocytosis by rat Kupffer cells.
Ca2+ uptake by monolayer cultures of rat Kupffer cells was strongly stimulated immediately after contact with phagocytosable material, e.g. zymosan particles. The intensity of the luminol-mediated chemiluminescence following zymosan addition was dependent on extracellular Ca2+; addition of the Ca2+-ionophore A 23187 did not further increase the zymosan-elicited response. The superoxide-mediated chemiluminescence was not inhibited by indomethacin but could be suppressed by compounds known to inhibit Ca2+-calmodulin-dependent reactions. Analysis of their efficiency, however, suggests that the O-2 production is mediated by Ca2+ rather than Ca2+-calmodulin and that the inhibitors exert another, e.g. membrane-directed influence.
D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D005260:Female; D007728:Kupffer Cells / Q000378:metabolism*; D008163:Luminescent Measurements; D010587:Phagocytosis; D051381:Rats; D011919:Rats, Inbred Strains; D013481:Superoxides / Q000378:metabolism; D015054:Zymosan / Q000494:pharmacology
D013481:Superoxides; D000001:Calcimycin; D015054:Zymosan; D002118:Calcium