Figure 6

Characteristics of perivascular astrocytes in the cervical and lumbar spinal cord of G93A mice. (A) Immunohistochemical staining of perivascular astrocytes with GFAP antibody (green) in control mice showed normal appearance of delineated astrocytes covering capillaries in the cervical (a,a’, arrowheads) and lumbar (f,f’, arrowheads) spinal cords. In media-injected mice, perivascular astrocytes surrounding capillaries were partially revealed in both the cervical (b,b’, arrowheads) and lumbar (g,g’, arrowheads) spinal cords. There were no substantial differences in perivascular astrocyte GFAP expressions in cervical (low dose; c,c’; mid dose: d,d’, arrowheads) or lumbar spinal (low dose; h,h’; mid dose: i,i’, arrowheads) cords compared to media-injected mice. In mice receiving high cell dose, numerous capillaries demonstrated typical perivascular astrocytes surrounding capillaries in both cervical (e, e’, arrowheads) and lumbar (j,j’, arrowheads) spinal cords. Scale bar in a–j’ is 50 µm. (B) Measures of GFAP perivascular immunoexpression showed significantly decreased fluorescence in the cervical and lumbar spinal cords of media-injected mice vs. controls. In the cervical spinal cord, significantly increased perivascular GFAP immunoexpressions were determined in mice receiving mid and high cell doses vs. media-injected animals. Also, perivascular GFAP intensity in high cell dose spinal cords was significantly greater compared to low or mid cell doses. In the lumbar spinal cord, no significant differences in perivascular GFAP fluorescent expression were found between media-injected, low, and mid cell doses. Only mice receiving the high cell dose exhibited a significant increase of perivascular immunoexpression vs. media-injected, low, or mid cell dose mouse groups. **p < 0.01, ***p < 0.001.