Fig. 1

The ERK signaling pathway. BDNF combines with its specific receptor Trk-B and the compound object can activate the Ras-dependent cascade. The Ras-dependent cascade is Ras-Raf-MEK-ERK signaling pathway. Phosphorylated ERK1/2 (p-ERK1/2) can further phosphorylate CREB and promote the transcription of BDNF mRNA. PD98059 prevents the ERK1/2 from being phosphorylated. Activating reactions were depicted by an arrow with a black color and the inhibiting effect of PD98059 was depicted by a line with a red color. The proteins involved in the present study were marked by a rectangle box with a black color. BDNF brain-derived neurotrophic factor, CREB cAMP response element-binding protein, ERK1/2 extracellular signal-regulated kinase 1/2, MEK ERK1/2 kinase, p-CREB phosphor-CREB, p-ERK1/2 phosphor-ERK 1/2, Trk-B tyrosine receptor kinase B