Table 2: Summary of changes in CREB phosphorylation in different brain regions following morphine treatment.

Brain regionNaïveSaline Morx1Morx8EscAcute PPAcute MPChronic PPChronic MP

AMGCCC
DMCCC
LHCCC
NAccCCC
VTAC CC

C: control; —: no change from appropriate control (saline versus naïve, Morx1, Morx8 and Esc versus saline, acute MP versus acute PP, chronic MP versus chronic MP), Morx1 single injection of morphine, Morx8, daily injection of morphine for 8 days, acute PP, 24 h placebo pellet, acute MP, 24 h morphine pellet, chronic PP, 7 day placebo pellet, chronic MP, and 7 day morphine pellet. AMG: amygdala; DM: dorsomedial hypothalamic nucleus; LH: lateral hypothalamus; NAcc: nucleus Accumbens; VTA: ventral tegmental area.