Western blot analysis shows the decreased t-ERK1/2 following ID and hypothyroidism (n = 3 for each group). The levels of t-ERK1/2 in ID and hypothyroidism groups were significantly lower than controls in CA1 and CA3 regions on PN14 (A), PN21 (B), PN28 (C) and PN42 (D). (a) Representative blots of t-ERK1/2 in hipocampal CA1, CA3 and DG regions of control, 5 ppm PTU-treatment, 15 ppm PTU-treatment and iodine-deficient groups. (b and c) t-ERK1 and t-ERK2 levels. Each bar represents the mean ± SEM. *P < 0.05, as compared to control.#P < 0.05, as compared to 5 ppm PTU-treatment group. ΔP < 0.05, as compared to 15 ppm PTU-treatment group.