Skip to main content
Fig. 4 | Molecular Autism

Fig. 4

From: The activation of mGluR4 rescues parallel fiber synaptic transmission and LTP, motor learning and social behavior in a mouse model of Fragile X Syndrome

Fig. 4

Reducing extracellular Ca2+ reduces asynchronous release and rescues isoproterenol-induced potentiation and PF-PC LTP at Fmr1KO slices. a Isoproterenol (100 μM, 10 min) enhances the sEPSC amplitude recorded in the presence of Sr2+ (1.0 mM). b Quantification of the effects of isoproterenol on sEPSC amplitude: (n = 6: **P < 0.01, unpaired Student’s t test). c Individual traces showing asynchronous release events in control (black) and after exposure to isoproterenol (red). d, f Quantification of the isoproterenol induced changes in aEPSC frequency (d) (n = 305 events/10 slices and n = 474 events/10 slices: two-way ANOVA followed by Tukey, *P < 0.05) and in aEPSC amplitude (f) (P > 0.05, unpaired Student’s t test). e, g Cumulative probability plots of isoproterenol induced changes in aEPSC frequency (inter event interval, IEI) (e) (***P < 0.001) and aEPSC amplitude (g) (P > 0.05, Kolmogorov–Smirnov test). h PF LTP was re-established in Fmr1KO slices, yet no LTP was induced in WT slices in the presence of 1 mM Ca2+. Experiments in Fmr1KO slices were also performed in the presence of the β-AR antagonist propranolol (100 µM, added 30 min prior to LTP induction). i Changes in EPSC amplitude (mean of 6 consecutive EPSCs delivered at 0.05 Hz) 30 min after stimulation (2) compared to basal (1): in Fmr1KO (n = 14 cells/14 slices/7 mice: ***P < 0.001, unpaired Student’s t test); in Fmr1KO slices treated with propranolol (n = 9 cells/9 slices/4 mice: P > 0.05, Welch test); and in WT (n = 10 cells/10 slices/4 mice: P > 0.05, unpaired Student’s t test). j Cumulative EPSC amplitudes (in the presence of 1 mM Ca2+) before and 30 min after LTP induction in Fmr1KO slices. RRP size was calculated from the cumulative amplitude plots as the y-intercept from a linear fit of the steady-state level attained during a train of 100 stimuli at 40 Hz. k Quantification of the RRP in Fmr1KO slices (n = 12 cells/12 slices/4 mice and n = 12 cells/12 slices/5 mice, before and after LTP induction: ***P < 0.001, Welch test). Bar graphs show raw data and the mean. Scale bar in a, c 10 pA and 100 ms; and in h 50 pA and 30 ms

Back to article page