Figure 1.
a) c-Fos activation by light is decreased in the binocular primary visual cortex of deprived animals both in the cortex contralateral (t test, P<0.001, N = 11) and ipsilateral (t test, P<0.001, N = 11) to the deprived eye; b) example of c-Fos staining after visual stimulation; c) high-magnification images showing the typical co-localization between c-Fos and PV.
Figure 2.
Contra/Ipsi ratio (C/I) of visual c-Fos induction in cortical neurons.
The ratio between the number of c-Fos positive cells activated by contralateral and ipsilateral stimulation is reported. The TOT bar corresponds to the total cortical population. The other columns report the data for c-Fos positive cells double-stained with GAD67, PV, CB or CR. No significant difference is present (one way ANOVA, P = 0.952).
Figure 3.
Effects of MD on inhibitory neuron markers.
Long-term MD has no effect (t test, p>0.05) on the expression of GAD67 (a), PV (b) and CR (c), while it decreases the number of CB immunoreactive cells (d) in both hemispheres (t test, contra to the deprived eye P = 0.005, and ipsi P = 0.019).
Figure 4.
Effect of long-term MD on the whole population of cortical inhibitory interneurons.
a) GAD67 cells show a reduction in the D/M ratio in both hemispheres of MD animals (contra, t test, P = 0.002; ipsi, t test, P = 0.037, N = 10); b) no difference is present in the D/F ratio of GAD67 cells between MD and control animals (contra, t test, P = 0.33; ipsi, t test, P = 0.76; N = 10).
Figure 5.
Effect of long-term MD on PV interneurons.
a) PV interneurons did not show a significant decrease in the D/M ratio after long-term MD (contra, t test, P = 0.19; ipsi, t test, P = 0.65; N = 11), indeed b) the proportion of c-Fos positive cells which were also PVergic (D/F ratio) was increased in MD rats (contra, t test, P = 0.017; ipsi, t test, P = 0.041; N = 11).
Figure 6.
Effect of long-term MD on calretinin interneurons.
CR interneurons show an analogous behaviour to the whole GABAergic population with a) a reduction in the D/M ratio (contra, t test, P = 0.003; N = 10) and b) lack of difference in the D/F ratio respect to control.
Figure 7.
PV cells show c-Fos activation by PTX similar to the other cortical neurons.
Dose-response curves after exposure to increasing concentrations (0, 0.2, 2, 20 µM) of PTX, showing comparable increases in c-Fos activation in the whole cortical cellular population (black) and in PVergic cells (red) (two-way ANOVA, effect of PTX concentration is significant with P = 0.003, while no significant effect of cell type and no interaction between cell type and PTX dose was present, P>0.05, N = 4). Data are normalized to the value obtained with stimulation with 20 µM PTX.