FIGURE 4.

Inhibition of synaptic vesicle exocytosis by isoflurane is attenuated by reducing endogenous BDNF. Rat hippocampal neuron cultures (16DIV) transfected with vGlut-pH and mCherry were perfused with control buffer, 0.5–0.7 mM isoflurane, or TrkB-Fc (1 μg/ml) + 0.5–0.7 mM isoflurane with tetanic stimulation (lightning bolt) as indicated in (A). (B) Synaptic vesicle exocytosis evoked by tetanic stimulation was reduced by isoflurane (0.5–0.7 mM) (**p< 0.01 by multiple comparisons one-way ANOVA with Dunnett’s post-hoc test). Reduced exocytosis observed with isoflurane exposure was attenuated by pretreatment with TrkB-Fc (1 μg/ml) for 5 min prior to stimulation (*p < 0.05 by multiple comparisons one-way ANOVA with Dunnett’s post-hoc test). Data are mean±SD; n = 8 neurons per experimental group and 327–400 boutons.