Fig 2: Dopaminergic signaling is impaired in the medial PFC of Col6a1–/– mice. (A) qRT-PCR analysis for Th, Slc6a3 and Nr4a2 mRNA levels in the medial PFC of wild-type and Col6a1–/– mice. *P<0.05; unpaired two-tailed Student's t-test; WT, n=11; Col6a1–/–, n=12. (B) Representative western blot (left) and densitometric analysis (right) of TH and DAT in the medial PFC of WT and Col6a1–/– mice. *P<0.05; unpaired two-tailed Student's t-test; WT, n=9; Col6a1–/– n=8. Error bars indicate s.e.m.

Fig 3: Effect of HD-tDCS application over the prefrontal cortex on TH- and DAT-positive cells in a rat model of ADHD.(A, E) Photomicrograph and histogram showing the mean IOD of TH- and DAT-positive cells in the medial prefrontal cortex, (B, F) in the striatum, (C, G) in the dorsal hippocampus, and (D, H) in the SN/VTA. The IOD of TH-positive cells was significantly increased in the medial prefrontal cortex and striatum of tDCS-PFC group compared to the sham results. The IOD of DAT-positive cells was significantly decreased in the medial prefrontal cortex, dorsal striatum, and SN/VTA in the tDCS-PFC group compared to the sham results. Data are presented as the mean ± SEM. mPFC, medial prefrontal cortex. &p<0.05 and &&p<0.01 vs. sham, $p<0.05 and $$p<0.01 vs. tDCS-PFC. Scale bar = 100 µm.Figure 3—source data 1.Source file for quantification of Iba1-, TH-, and DAT-positive cells.This zip archive contains all source data for Iba1-, TH-, and DAT-positive cells analysis shown in Figure 3, and Figure 3—figure supplements 1 and 2.

Fig 4: SS alters the transcriptome in the developing male VTA. A SS and CTR male VTA were collected at PD22 (n = 4/group). The drawing shows the location of the punches (bilateral 0.5 mm circular sampling). RNA-sequencing revealed 81 differentially expressed genes (DEGs) between the two groups. B Heatmap and C volcano plot of the DEGs. Downregulated genes in SS are highlighted in blue and upregulated genes are red (p adjusted < 0.05). Not significantly modulated genes are shown in black. Selected genes of relevant pathways have been labeled. D Table with log2(fold change) values of dopaminergic DEGs and statistical significance (SS relative to CTR, p adjusted). Slc6a3, dopamine transporter; Slc18a2, vesicular monoamine transporter member 2; Ddc, dopa decarboxylase; Th, tyrosine hydroxylase; Ret, RET receptor tyrosine kinase; Aldh1a1, aldehyde dehydrogenase 1 family member A1; En2, engrailed homeobox 2; Pitx3, paired like homeodomain 3; En1, engrailed homeobox 1; Drd2, dopamine receptor D2; Chrnb3, neuronal acetylcholine (nicotine) receptor subunit beta-3; Gucy2c, peptide guanylate cyclase 2c; Chrna6, cholinergic receptor nicotinic alpha 6 subunit; Gch1, GTP cyclohydrolase 1; Ndnf, neuron-derived neurotrophic factor; Cplx1, complexin 1; Chrna4, cholinergic receptor nicotinic alpha 4 subunit; Cplx2, complexin 2; Trh, thyrotropin releasing hormone; Tac2, tachykinin 2; Crhbp, corticotropin releasing hormone binding protein

Fig 5: Minocycline treatment reverts dopaminergic aberrations induced by SS. A Minocycline was daily administered through intraperitoneal (i.p.) injection to male CTR and SS mice from PD14 to 21. Analyses were performed in the VTA at PD22. B–E Lower and higher (insets) magnification of B TH-IHC stained neurons, and C–E DAT and TH immunofluorescence in the VTA (coronal hemisection) of CTR, CTR-minocycline (CTR-mino), SS, and SS-minocycline (SS-mino) male pups. F Minocycline in SS mice restored roundness of dopaminergic neurons to CTR levels (MANOVA univariate group*treatment effect, P < 0.01). G, H In SS-mino mice, DAT, and TH immunoreactivity were significantly increased with respect to SS mice, to levels comparable to or above CTR mice. F N = 3–6 animals/group; 6 hemisections/animal. Dots in the graphs represent average value for each hemisection. Univariate group*treatment effect: ## P < 0.01; Tukey HSD test: *P < 0.05. G, H N = 3–5 animals/group; 4–6 sections/animal. Dots in the graphs represent value for each section. Group*treatment effect: ### P < 0.001; group effect: $ P < 0.05; Tukey HSD test: *P < 0.05, **P < 0.01, ***P < 0.001. Data are presented as mean ± s.e.m. Scale bars = (B-E) 100 µm, (B, E insets) 20 µm