Figure 1

Astrocyte Specific Attenuation of Gliotransmission Causes Reduced Basal Nociception but Does Not Alter NPP. (A) The lumbar spinal cord exhibits abundant expression of EGFP reporter protein (green) with distinct colocalization with the astrocyte marker, GFAP (red; left), but not with the neuronal marker NeuN (red; right). (B) Quantification of EGFP+ cells reveals that 69.2 ± 7.3% GFAP+ cells were EGFP+ in dnSNARE mice but 0% colocalization was present Iba1+ or NeuN+ cells. No EGFP+ cells were found in WT sections (not shown). (C) dnSNARE expression does not cause reactive astrocytes or microglia as shown by similar GFAP (WT: 22.7 ± 2.4% n = 3; dnSNARE: 20.6 ± 1.2% n = 3; P = 0.24) and Iba1 (WT: 10.7 ± 0.5% n = 3; dnSNARE: 10.3 ± 0.2% n = 3; P = 0.20) staining between dnSNARE and WT dorsal horns. (D) DnSNARE mice exhibit a significant reduction in baseline paw withdrawal thresholds compared to WT mice (WT: 1.24 ± 0.13 n = 18, dnSNARE: 0.86 ± 0.08 n = 21 *P < 0.01). (E) DnSNARE and WT mice both exhibit sustained reduction in paw withdrawal threshold after SNI with no significant difference between WT and dnSNARE (WT: n = 9 for 3-21 dpi, n = 7 for 28 dpi dnSNARE: n = 12 for 3-21 dpi, n = 7 for 28 dpi P = 0.570). Scale bars: 10 μm (upper); 100 μm (lower). dpi, days post injury.