Journal: The Journal of Headache and Pain

Article Title: Downregulation of neuronal DRD2 drives microglia synaptic pruning and results in cognitive deficits by promoting CCL2 release in a rat model of chronic migraine

doi: 10.1186/s10194-025-02229-3

Figure Lengend Snippet: Chronic intrathecal is administration resulted in reduced DRD2 expression in the dentate gyrus and impaired cognitive function. ( A )–( B ) The Hind paw Mechanical and thermal pain thresholds in rats treated with is injection were markedly lower than those in sham rats. Data analyzed by two-way anova with Bonferroni correction; n = 6 rats per group. * p < 0.05, ** p < 0.01 and *** p < 0.001 as compared to sham rats. ( C )–( E ) Representative immunoblots and quantification illustrated decreased levels of DRD2 in the hippocampus and increased levels of CGRP in the tnc after repeated dural is stimulation; n = 6 rats per group. ( F ) RT-qPCR results showed that the mRNA expression of DRD2 in the hippocampus decreased in the CM group compared with the sham group. n = 6 rats per group. ( G )–( J ) Immunofluorescence labeling of DRD2 and neuronal markers (NeuN) in hippocampal subregions CA1, CA3, and DG, with quantitative evaluation of DRD2 fluorescence intensity; n = 4 rats per group. ( K ) A higher ratio of path length in the target quadrant in the sham group compared to the CM group during the probe trial. ( L ) Representative movement trajectories from the Morris water maze test for sham and CM groups. ( M ) IS rats showed increased escape latency relative to sham rats on the third day. Two-way anova followed by Tukey’s test; n = 8 rats per group. ( N ) Rats in the CM group spent significantly less time in the target quadrant during the probe test; data represent mean ± sem; unpaired Student’s t-test; ( O ) IS rats showed fewer platform crossings during the test session relative to sham controls. n = 8 rats per group. ( P ) IS rats showed significantly more non-spatial strategies compared to sham controls. Chi-square test of independence, χ 2 = 8.727, p = 0.0031; n = 8 rats per group. ( Q ) Thermal maps illustrating the exploration behavior of sham and is rats during the novel object recognition test. ( R ) The CM group showed a lower discrimination index during the nor test. ( S ) The CM group exhibited a lower recognition ratio during the novel object recognition test. All values represent mean ± sem; unpaired Student’s t-test unless noted; n = 8 per group; * p < 0.05, ** p < 0.01, *** p < 0.001 compared to sham group

Article Snippet: DRD2 , Santa Cruz, USA , Sc-5303 , Mouse , 1:200.

Techniques: Expressing, Injection, Western Blot, Quantitative RT-PCR, Immunofluorescence, Labeling, Fluorescence

Journal: The Journal of Headache and Pain

Article Title: Downregulation of neuronal DRD2 drives microglia synaptic pruning and results in cognitive deficits by promoting CCL2 release in a rat model of chronic migraine

doi: 10.1186/s10194-025-02229-3

Figure Lengend Snippet: Transcriptome analysis shows increased phagocytosis and chemokine signalling activation in glial cells in the hippocampus of is rats. ( A ) Volcano plot of differentially expressed genes (DEGs) in DRD2-KO versus wt mice. (|log₂FC| ≥ 1, FDR-adjusted p < 0.05; 846 total DEGs: 665 upregulated, 181 downregulated). ( B ) KEGG enrichment analysis highlights neuroinflammation, chemokine signalling, and microglia-related pathways (phagocytosis, protein digestion) in DRD2 ko mice. ( C ) GO analysis confirms microglial activation and phagocytosis in DRD2 ko mice. ( D ) Heatmap of key genes in the phagosome pathway. n = 3 mice per group. ( E ) Representative microglia (Iba1 + , red) immunofluorescence in hippocampal dg of WT and DRD2 ko groups. The boxed region is magnified (right). Scale bars: 100 μm (left), 20 μm (right). ( F ) Sholl analysis of microglia and a concentric circle diagram of WT and DRD2 ko groups. ( G ) No significant difference was found in the quantification of microglia in the dg area of the hippocampus between the two groups of mice.12 fields of view from 4 mice per group. ( H ) and( I ) Sholl analysis of the branch length and intersections of microglia in the dg of the hippocampus in WT and DRD2 ko groups. n = 20 microglia from 4 mice per group. ( J ) The average number of PSD95 + puncta per microglial cell was quantified in WT and DRD2 KO groups. ( K ) Representative 3D-rendered maximum projection of a confocal z-stack showing Iba1 and PSD95 in the dg of WT and DRD2 KO groups. Arrowheads indicate examples of PSD95 + puncta within Iba1 + microglial processes. ( L ) Volume ratio of engulfed PSD95 to total microglial cell volume. Data are shown as mean ± sem; unpaired Student's t-test; ** p < 0.01, *** p < 0.001 versus WT, n = 18 cells from 4 mice per group

Article Snippet: DRD2 , Santa Cruz, USA , Sc-5303 , Mouse , 1:200.

Techniques: Activation Assay, Immunofluorescence

Journal: The Journal of Headache and Pain

Article Title: Downregulation of neuronal DRD2 drives microglia synaptic pruning and results in cognitive deficits by promoting CCL2 release in a rat model of chronic migraine

doi: 10.1186/s10194-025-02229-3

Figure Lengend Snippet: Modulation of DRD2 signalling alters microglial phagocytosis, synaptic density, and cognitive function in a rat model of CM ( A ) and ( B ) Western blot and quantification of PSD95 expression in the hippocampus. Quinpirole restored PSD95 levels in the dg of is rats, while sulpiride worsened it; n = 6 rats per group. ( C ) and ( D ) Representative golgi-stained images of hippocampal dendrites. Quinpirole lessened dendritic spine loss in is rats, whereas sulpiride intensified it. Scale bar: 5 μm; 20 dendrites from 4 rats. ( E ) and ( F ) Immunofluorescence co-labelling of Iba1 + (green) and CD68 + (red) microglia in the dg. White arrows point to CD68 + microglia. Quinpirole lowered CD68 expression, while sulpiride increased it; n = 12 fields from 4rats per group. ( G ) Representative 3D-rendered confocal maximum projection of Iba1 and PSD95 in the dg. Arrowheads highlight PSD95 + puncta inside microglial processes. ( H ) Quinpirole reduced, whereas sulpiride increased, the volume ratio of engulfed PSD95 to total microglia. ( I ) The number of PSD95 + puncta per microglia. Quinpirole reduced microglial phagocytosis of PSD95 in is rats; sulpiride enhanced it; n = 18 cells from 4 rats per group. ( J ) Example paths of rats in the MWM test phase. ( K ) escape latency during MWM learning. Quinpirole decreased latency in is rats. ( L ) The distance travelled in the target quadrant is relative to the total distance. ( M ) Quinpirole treatment prolonged the time spent in the target quadrant by is rats. ( N ) The number of platform crossings in quinpirole-treated rats showed an increasing trend. Quinpirole improved all these parameters in is rats. ( O ) The discrimination index of quinpirole-treated rats was higher than that of CM-treated rats in the nort. ( P ) The recognition ratio during nort. Quinpirole increased both measures in is rats; n = 8 rats per group. Data are presented as mean ± sem. * p < 0.05, ** p < 0.01, *** p < 0.001; unpaired Student’s t-test (A–I, L–P); two-way anova with Tukey’s post hoc test ( k )

Article Snippet: DRD2 , Santa Cruz, USA , Sc-5303 , Mouse , 1:200.

Techniques: Western Blot, Expressing, Staining, Immunofluorescence

Journal: The Journal of Headache and Pain

Article Title: Downregulation of neuronal DRD2 drives microglia synaptic pruning and results in cognitive deficits by promoting CCL2 release in a rat model of chronic migraine

doi: 10.1186/s10194-025-02229-3

Figure Lengend Snippet: IS rats exhibit elevated CCL2 expression in hippocampal neurons, which DRD2 regulates. ( A ) Heat map of transcription levels of chemokine and complement genes associated with synaptic pruning in the hippocampus of DRD2 ko mice. ( B ) IS rats exhibit elevated hippocampal mRNA expression of chemokines associated with synaptic pruning; n = 6 rats per group. ( C ) and ( D ) Immunofluorescence co-labelling of neurons (green) and CCL2 (red) in the dg. Quinpirole decreased CCL2 expression in neurons, while sulpiride increased it. Scale bar = 100 μm, n = 4 rats per group. ( E ) Representative immunofluorescence image showing co-localization of dg microglia (green) and CCR2 (red) (indicated by white arrows). Data are shown as mean ± sem, with unpaired Student's t-test, * p < 0.05, ** p < 0.01, *** p < 0.001

Article Snippet: DRD2 , Santa Cruz, USA , Sc-5303 , Mouse , 1:200.

Techniques: Expressing, Immunofluorescence