Dendritic tree of striatal interneurons. (A, B) Microphotographs showing the parvalbumin immunostaining of the caudate in two representative sections from an ethanol-treated (A) and a control (B) animal. Scale bar = 50 μm. (C, D) The same sections shown in A and B, after application of the threshold algorithm, in order to quantify the area covered by immunostaining. Scale bar = 50 μm. (E) Average percentage of the image area covered by immunostaining (two frames per section; width: 640 μm; height: 380 μm; four sections per case). * P <0.05 at the ANOVA for nested design. (F) Dendrograms of two representative neurons, from an ethanol-treated and a control animal. (G) Average length of the dendritic tree of each neuron (five neurons per section; four sections per case). **P <0.01 at the ANOVA for nested design. (H) Sholl analysis performed with circles of 10 μm, 20 μm and 30 μm radius. Error bars represent standard error of the mean. Differences between the two groups were evaluated with the Mann–Whitney U test (*P < 0.05; **p <0.01). (I) Bar graphs showing quantitative parameters for completely reconstructed dendrites. The average number of primary dendrites per neuron is represented in the last bar graph. *P <0.05.