Seizure-Induced Regulations of Amyloid-β, STEP₆₁, and STEP₆₁ Substrates Involved in Hippocampal Synaptic Plasticity

Figure 4

A single ECS and chronic ECS differently alter Tyr^204/187-phosphorylation of ERK1/2 in the hippocampus. Immunoblot analysis for the phosphorylation of ERK1/2 at Tyr^204/187 (Y^204/187) and total ERK1/2 expression in the hippocampal crude membrane (P2) fraction following a single ECS ( rats per time point) (a) and chronic ECS ( rats per time point) (b). The ratio of the Tyr^204/187-phosphorylated ERK1/2 band intensity over the β-actin band intensity (top graphs) and the ratio of total ERK1/2 band intensity over the β-actin band intensity (bottom graphs) were calculated per each time point and normalized to that of “no seizure” (NS) sham group. Data shown represent the mean band intensity ± SEM. (a) A single ECS transiently decreases the level of Tyr^204/187-phosphorylated ERK1/2 in the hippocampus at 48 h (, -test) and total ERK1/2 expression at 72–96 h () following a single ECS. (b) Chronic ECS significantly increases the level of Tyr^204/187-phosphorylated ERK1/2 at 0 h following chronic ECS () but has no effect on total GluN2B expression in the hippocampus.

(a)

(b)