Fig. 7

Differences between male and female rats in the Akt/GSK3/β-catenin signaling pathway. Modulation of GSK3/β-catenin. Western blot analysis of phospho-GSK3 (pGSK, a, b), β-catenin (c) and phospho-Akt (pAkt) at two sites, threonine 743 (pThr743-Akt, D, left panel) and serine 308 (pSer308-Akt, E, right panel) in male and female rats. These animals were treated for five days with vehicle, SKF 83959 (SKF59) or pre-treated with TAT-D1 followed with SKF 83959 (SKF59 + TAT-D1). N = 6/group. a In the NAc, the basal phosphorylation of both isoforms of GSK3, pGSKα (p < 0.01), and pGSKβ (p < 0.01) were lower in female compared to male rats. Similar results were observed in the CPu (p < 0.01). b In the NAc of male rats (7b, left panels) repeated treatment with SKF 83959 (0.4 mg/kg × 5 days) increased pGSKβ in comparison to vehicle-treated rats (p < 0.005), which was inhibited by pre-treatment with TAT-D1 peptide (p < 0.05). In the NAc of female rats (5b, right panel), SKF 83959 induced a significant decrease in pGSKβ (p < 0.05), which was blocked by pre-treatment with TAT-D1 (p < 0.05). c In male rats (7c, left panel), treatment with SKF 83959 alone or after pre-treatment with TAT-D1 had no significant effect on β-catenin expression in the NAc (p < 0.05). In the NAc of female rats (7c, right panel), SKF 83959 decreased β-catenin expression (p > 0.05)