The role of PKC and PKD in PLD stimulation. (A) The effect of the nPKC inhibitor, GF109203X, and the cPKC and PKD inhibitor, Gö6076, on orexin- and TPA-induced PLD activities. (B) The effect of dominant-negative PKD constructs on orexin- and TPA-induced PLD activities. (C) PLD activity in response to the peptide PKC activators of PKCδ (KAD1-1), PKCε (KAE1-1) and cPKC (KAC1-1) as compared with orexin-A and TPA. (D) The effect of the peptide PKC inhibitors of PKCε (KIE1-1) and cPKC (KIC1-1) on orexin-, TPA- and KAE1-1-induced PLD activity. Please note that the effect of KIC1-1 on KAE1-1 was not tested, and thus that column is altogether missing. The comparisons are to the corresponding controls (same stimuli in the absence of the inhibitor) (A, B, D) or to the basal (C). ns, not significant; *P < 0.05; **P < 0.01; ***P < 0.001.