Expression of IGF-1 in serum and phosphorylated IGF-1 receptor in spinal cord in mouse model of bone cancer pain / 中华行为医学与脑科学杂志

ABSTRACT

Objective To investigate the expression of insulin-like growth factors-1(IGF-1)in ser-um and phosphorylated IGF-1 receptor in spinal cord in mouse model of bone cancer pain. Methods Sixty male C3H/HeJ mice weighed 18-22 g were randomly divided into Sham group(n=30)and Tumor group(n=30). The mice in Tumor group were inoculated with NCTC fibrosarcoma cells in the right femur bone marrow cavity. Paw withdrawl mechanical threshold(PWMT)and the number of spontaneous flinches(NSF)were measured on 1d before inoculation and on 4 d,7 d,10 d,14 d,21 d after inoculation(n=8). At each time point,the mice of each group were taken blood by removal eyeball and the samples of blood were obtained to detect the expression of IGF-1 by enzyme-linked immunosorbent assay(n=4). The mice after taken blood on 14 d after inoculation were perfused and the samples of spinal cord lumber(L3~5)segment were obtained to detect the expression of phosphorylated IGF-1 receptor by immunofluorescence assay(n=6). Results Com-pared with Sham group,PWMT was significantly decreased(P<0.05)and NSF was significantly increased(P<0.05)on 7~21 d after inoculation. Compared with baseline value and Sham group(baseline value(27.33± 0.52)pg/ml,Sham group(29.11±1.86)pg/ml,(24.51±3.61)pg/ml,(23.33±4.59)pg/ml,(25.29±2.99) pg/ml),the expression of IGF-1 in serum was significantly increased on 7~21 d after inoculation in Tumor group((39.76±3.92)pg/ml,(36.93±2.18)pg/ml,(38.85±2.40)pg/ml,(39.70±2.62)pg/ml). The mean fluorescence intensity of phosphorylated IGF-1 receptor was significantly higher on 14d after inoculation in Tumor group(2.40±0.11)compared with Sham group(0.05±0.01). Conclusion Expression of IGF-1 in serum and phosphorylated IGF-1 receptor in spinal cord were significantly increased in mice with bone cancer pain,and this change may be involved in the development and maintenance of bone cancer pain.