Figure 2

Measurement of IGF-1 in mouse serum. Mouse serum IGF-1 was measured using (A) radioimmuno assay and (B) CNT-FET. The impedance value for each IGF-1 measurement was normalized to the corresponding PBS baseline value. Both assays show an increase in the serum IGF-1 at 6 months compared to 3 months. Between After 6 and 12 months there is not a significant difference in the IGF levels between the age groups. Statistical differences among groups were analyzed using GraphPad Prism t tests (GraphPad Software, San Diego, CA). The values represent the average of ≥ 4 measurements ± standard error of the mean (SEM). Significance of P ≤ 0.05 is indicated with an asterisk.