BAPTA induces a decrease of intracellular free calcium and a translocation and inactivation of protein kinase C in macrophages.
Addition of BAPTA/AM to liver macrophages lowered the level of [Ca2+]i and induced a translocation and inactivation of protein kinase C. The phorbol ester- and zymosan-induced release of arachidonic acid, prostaglandin E2 and superoxide, the formation of inositol phosphates upon addition of zymosan and the lipopolysaccharide-induced synthesis of TNF-alpha was inhibited by pretreatment of the cells with BAPTA/AM. Simultaneous addition of A23187 to elevate [Ca]i could not reverse the inhibitory effect of BAPTA. Phagocytosis of zymosan and formation of prostaglandin E2 from exogenously added arachidonic acid or upon addition of A 2187 was not altered by BAPTA/AM. No protein kinase C activity could be measured in homogenates obtained from BAPTA/AM-pretreated cells. These results indicate that the action of BAPTA in eucaryotic cells is not limited to its chelating effect on calcium but that BAPTA leads to a translocation and inactivation of protein kinase C.
Institut für Molekulare Zellbiologie, Freiburg, Germany.
P
P
Dieter
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E
Fitzke
J
J
Duyster
D000345:Affinity Labels / Q000494:pharmacology*; D000818:Animals; D015153:Blotting, Western; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D015232:Dinoprostone / Q000378:metabolism; D004533:Egtazic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D066298:In Vitro Techniques; D008099:Liver / Q000166:cytology / Q000187:drug effects; D008264:Macrophages / Q000187:drug effects / Q000201:enzymology*; D010587:Phagocytosis / Q000187:drug effects; D010703:Phorbol Esters / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors* / Q000378:metabolism; D051381:Rats; D013481:Superoxides / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis; D015054:Zymosan / Q000494:pharmacology
D000345:Affinity Labels; D010703:Phorbol Esters; D014409:Tumor Necrosis Factor-alpha; D013481:Superoxides; C070379:1,2-bis(2-aminophenoxy)ethane N,N,N',N'-tetraacetic acid acetoxymethyl ester; D000001:Calcimycin; D004533:Egtazic Acid; D015054:Zymosan; D011493:Protein Kinase C; D015232:Dinoprostone; D002118:Calcium