Influence of Triiodothyronine on Swimming Behavior of Neonatal Mice with Excitotoxicity Brain Injury

Objective To investigate the impact of triiodothyronine(T3) on swimming behavior of neonatal mice with excitotoxicity brain injury.Methods Seventy-one 5-days old(P5) neonatal mice were randomly divided into control group,model group,and treatment group.In treatment group,all pups were given intraperitoneal injection with left-triiodothyronine(L-T3) at 1 hour,24 hours,48 hours,72 hours and 96 hours after receiving intracerebral injection of 2 μg·kg-1,5 μg·kg-1 and 10 μg·kg-1 ibotenic acid (IA),subdivided into low-dese group,medium-dose group and high-dose group.In control group,IA and L-T3 were replaced with PBS to injection to the mice.Each group were compared for the differences in swimming behavior at 10 days(P10 )and 12 days(P12) after birth.Results Swimming test total scores at P10:there was no significant difference in scores between model group and low-dose group,medium-dose group,high-dose group respectively(Pa0.05).Swimming test total scores at P12:there was no significant difference in scores between model group and low-dose group,medium-dose group,high-dose group,respectively(Pa0.05),but the scores of high-dose group were higher than that of the model group(P0.05).Limb movement scores at P10:there was no significant difference in scores between model group and low-dose group,medium-dose group and high-dose group respectively(Pa0.05).Limb movement scores at P12:there was no significant difference of scores between model group and low-dose group(P0.05),but the scores of medium-dose group were higher than that of the model group(P0.05),and the scores of high-dose group were significantly higher than that of the model group(P0.01).Conclusion High dose T3 promoted swimming behavior of mice with the excitoxicity brain damage.