Fig. 4.

Representative autoradiograms of BDNF mRNA expression in the rat frontal cortex (a and b). BDNF mRNA expression was determined 3 h after i.c.v. administration of (+)BW373U86. Radiolabeled BDNF cRNA probes were used for in situ hybridization. (A) Section of frontal cortex taken from a vehicle-treated animal. (B) Section of frontal cortex taken from an animal treated with (+)BW373U86 (100 nmol, i.c.v.). Quantification of BDNF mRNA signals in different brain regions including frontal cortex (F.Ctx), CA1, CA3 and dentate gyrus (DG) of hippocampus, and amygdala (Amyg) are represented as mean percent of vehicle ± SEM (n = 4–6). **P < 0.01 compared with vehicle.