Fig. 6.
MEK-dependent decrease of c-Fos and GluR2 levels after fear extinction. (A) The activity of c-Fos in dorsohippocampal nuclear extracts was significantly lower in the E when compared to the T group (F2,15 = 11.19, p < 0.001). The AP-1 binding and c-Fos levels were increased after inhibition of the MEK/ERK pathway. (B) The level of GluR2 increased in the T group (F2,15 = 6.67, p < 0.01) but this increase was reversed in the E group. After inhibition of the hippocampal MEK/ERK pathway by U0126, the level of GluR2 remained elevated (F2,15 = 15.67, p < 0.001. Statistically significant differences: *p < 0.001 all other groups.