Fig. 2

Differences in synaptic bouton unloading of FM1-43 dye in hippocampal (HC) and cerebellar (CB) neurons. (top left) Weak unloading boutons are less synaptically active, which translates into the release of fewer synaptic vesicles and neurotransmitters. Strong unloading boutons have a greater number of synaptic vesicle exocytosis and are therefore expected to release neurotransmitters more actively. Kinetics of FM1-43 unloading of weak unloading boutons in the hippocampus showed a significant difference with a p value of 0.004 during stimulation with 50 mM KCl and (top right) a significant difference with a p value of 0.008 for strong unloading boutons in the hippocampus. In the cerebellum, the weak unloading boutons showed a highly significant change with a p value of 2.17 × 10⁻⁹ (below left), as well as a highly significant change with a p value of 2 × 10⁻¹⁶ for strong unloading of FM1-43 dye from synaptic boutons (below right). The p values were obtained by regression analysis with ANOVA comparing Fmr1 KO with WT mouse primary neurons