Fig. 5: GABAergic activity-dependent inhibitory neurotransmission is affected in SMA motor CRTX.
From: Changes in the cortical GABAergic inhibitory system in a Spinal Muscular Atrophy mouse model
a Representative immunofluorescence images of biocytin-labelled motor cortex pyramidal neurons. Scale bar: 100 um. b Representative recording of sIPSCs (above) and mIPSCs (below) from a pyramidal neuron of a WT mouse. c. Representative recording of sIPSCs (above) and mIPSCs (below) from a pyramidal neuron of a SMA mouse. Recordings were performed as in G. d Cumulative distribution of sIPSCs and mIPSCs interevent intervals (ms) from the neuron in (b). TTX induced a clear right-shift of the interevent interval distribution (Kolmogorov-Smirnov test, p < 0.001). e Cumulative distribution of sIPSCs and mIPSCs interevent intervals (ms) from the neuron in (c) In this case, the distributions of interevent intervals were not affected by TTX (Kolmogorov-Smirnov test, p < 0.91). f Percentage of pyramidal neurons in which TTX significantly affected interevent interval (and hence frequency) of inhibitory currents (significant if K-S with p < 0.01). In WT mice, TTX decreased IPSC frequency in 100% of the recorded neurons (9 out of 9). Conversely, in SMA mice TTX affected IPSC frequency in only 56% of the recorded neurons (6 out of 11). g Multiple comparisons of mean IPSC frequency across genotypes before and after TTX (each dot represents a single recorded cell. Two-way ANOVA followed by Fisher’s post-hoc test; *p < 0.05; **p < 0.01; ***p < 0.0001; WT/ SMA mice: n = 4). h Multiple comparisons of mean IPSC amplitude across genotypes before and after TTX (each dot represents a single recorded cell. Two-way ANOVA followed by Fisher’s post-hoc test; *p < 0.05; **p < 0.01; ****p < 0.0001, ns: not significant; WT/ SMA mice: n = 4).
