ABSTRACT
Objective:To investigate the role of NG2 cells in generating and maintaining neuropathic pain in rats after spinal cord injury (SCI).Methods:According to random number table method, 100 healthy adult male SD rats were divided into control group ( n=20, without any intervention), sham-operated group ( n=40, exposed T 10 segment without spinal cord impact) and SCI group ( n=40, exposed T 10 segment and constructed SCI model by improved Allen's method). One d before, and 14, 21 and 28 d after surgery, Von Frey fiber probe was used to detect the rat hindlimb mechanical withdrawal threshold (MWT); immunofluorescent staining was used to detect the proportion of NG2-positive cells in spinal dorsal horn cells; Western blotting was used to detect chondroitin sulfate proteoglycan (CSPG) expression in spinal dorsal horn of rats. Results:Fourteen, 21 and 28 d after surgery, SCI group had significantly lower hindlimb MWT, and significantly higher proportion of NG2-positive cells in spinal dorsal horn cells and CSPG expression in spinal dorsal horn than control group and sham-operated group ( P<0.05). One d before, and 14, 21 and 28 d after surgery, in SCI group, hindlimb MWT decreased firstly and increased secondly, proportion of NG2-positive cells in spinal dorsal horn cells increased firstly and decreased secondly, and CSPG expression in spinal dorsal horn increased firstly and decreased secondly. Except for those 21 and 28 d after surgery, hindlimb MWT, proportion of NG2-positive cells in spinal dorsal horn cells, and CSPG expression in spinal dorsal horn showed significant differences between each two time points ( P<0.05). In SCI group, hindlimb MWT was negatively correlated with proportion of NG2-positive cells in spinal dorsal horn cells ( r=-0.876, P<0.001), and CSPG expression was positively correlated with proportion of NG2-positive cells in spinal dorsal horn cells ( r=0.927, P<0.001). Conclusion:NG2 cell proliferation and increased CSPG expression secreted by NG2 cells in spinal cord tissues after SCI generate and maintain neuropathic pain.
ABSTRACT
Objective To accumulate data for the physical anthropology research of Miao ethnicity adults , and find out the kinship and difference between this group and the other 10 ethnicities.Methods Viviperception and measurement were used to study the caudomedial part traits in 299 Miao ethnicity adults (146 males and 153 females ) who lived in Chishui city in Guizhou , and statistical software SPSS18.0 was used to process data .Results Apart from length of middle finger , the height of medial malleolus subpoint , and the rest 19 indices between male and female had significant difference or great significant difference (0.01