Agmatine decreased glutamate release and increased glutamate uptake of hippocampal synaptosomes from chronic morphine-treated rats. A Effect of agmatine on glutamate release in chronic morphine-treated rats. B Effect of agmatine on the uptake of [3H]-glutamate in synaptosomes from chronic morphine-treated rats (n = 9; *P < 0.05 vs Con group, #
P < 0.05 vs Mor group, one-way ANOVA followed by Bonferroni test). Con control, Mor morphine, Agm agmatine, Agm + Mor agmatine administered with morphine for 5 days.