Figure 9: Treatment with the Pi infusion increases the levels of GDNF transcript in primary astrocytes. Rat primary astrocytes were exposed to 250 Mg/mL of Pi infusion for 9 or 24 h. Total RNA was then extracted. GDNF transcripts were measured using quantitative realtime PCR. The results of three technical replicates were normalized to glyceraldehyde3phosphate (GAPDH) and are expressed as relative quantities of GDNF transcripts. The results are means ± SD of one out of three experiments. Meanspaired, onetailed ttests were used to evaluate the effects of the infusion on the expression of GDNF and the effect of the duration of the incubation. These tests yielded P(t) values of 0.029 and 0.105, respectively. Therefore, we can conclude that, in cases in which the effect of the duration is not statistically significant, the effect of the Pi infusion is significant at a 95% significance level. 
