Figure 3.

Photomicrographs of brain-derived neurotrophic factor (BDNF)-, phosphorylated cAMP response element binding protein (pCREB)- and phosphorylated extracellular signal-regulated kinase (pERK)-positive cells in the hippocampal CA1 region (A). Tanshinone I (4 mg·kg⁻¹, p.o.) was administered 40 min before transcardial perfusion. Summary data of the numbers of BDNF- (B), pCREB- (C) and pERK- (D) positive cells in CA1. Data represent means ± SEM for six determinations in each region for four animals. *P < 0.05, compared with untreated controls. Magnification: 1000×. Bar = 50 µm.