Different roles of protein kinase C-beta and -delta in arachidonic acid cascade, superoxide formation and phosphoinositide hydrolysis.
In contrast with protein kinase C (PKC)-beta, PKC-delta is exclusively detectable in the membrane fraction of liver macrophages. After long-term treatment with phorbol 12-myristate 13-acetate (PMA) PKC-beta is depleted faster (within 3 h) than PKC-delta (> 7h). Simultaneously, pretreatment with PMA for 3 h inhibits the PMA- and zymosan-induced generation of superoxide and the PMA-induced formation of prostaglandin (PG) E2, whereas a preincubation of more than 7 h is required to affect the zymosan-induced release of PGE2 and inositol phosphates. These results support an involvement of PKC-beta in the PMA-induced activation of the arachidonic acid cascade and in superoxide formation and imply an involvement of PKC-delta in zymosan-induced phosphoinositide hydrolysis and PGE2 formation. Two phorbol ester derivates, sapintoxin A (SAPA) and 12-deoxyphorbol 13-phenylacetate 20-acetate (DOPPA), which have been previously reported to activate preferentially PLC-beta but not PKC-delta in vitro [Ryves, Evans, Olivier, Parker and Evans (1992) FEBS Lett. 288, 5-9], induce the formation of PGE2 and superoxide, down-regulate PKC-delta and potentiate inositol phosphate formation in parallel SAPA, but not DOPPA, down-regulates PKC-beta and inhibits the PMA-induced formation of eicosanoids and superoxide.
Institut für Molekulare Zellbiologie, Freiburg, Germany.
J
J
Duyster
H
H
Schwende
E
E
Fitzke
H
H
Hidaka
P
P
Dieter
D000818:Animals; D016718:Arachidonic Acid / Q000378:metabolism*; D002478:Cells, Cultured; D006868:Hydrolysis; D007527:Isoenzymes / Q000378:metabolism*; D008099:Liver / Q000166:cytology; D008264:Macrophages / Q000201:enzymology; D008297:Male; D010703:Phorbol Esters / Q000494:pharmacology; D010716:Phosphatidylinositols / Q000378:metabolism*; D011493:Protein Kinase C / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D015398:Signal Transduction; D013481:Superoxides / Q000378:metabolism*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D007527:Isoenzymes; D010703:Phorbol Esters; D010716:Phosphatidylinositols; D013481:Superoxides; D016718:Arachidonic Acid; C029704:12-deoxyphorbolphenylacetate; C032016:sapintoxin A; D011493:Protein Kinase C; D013755:Tetradecanoylphorbol Acetate