Objective to investigate the effects on P-Akt of short-time postinsult treatment with lithium in a rat model of middle cerebral artery occulsion/reperfusion. Methods Inserted with a nylon the right middle cerebral artery of rats was occluded for 1.5h, then recirculation was instituted for various times before death. Experiment 1: SD rats were randomly divided into five subgroups: LI0(0mmol/kg), LI0.5(0.5mmol/kg), LI1(1mmol/kg), LI3(3mmol/kg) andLI5(0mmol/kg), and they were killed two days after ischemic insult. Six rats were used in each subgroup. Experiment 2: SD rats were randomly divided into two groups: ischemia-reperfusion group (IR group) and postinsult treatment with lithium group (LI group, LI = 3mmol/kg). According to the time when they were killed, they were further divided into 4 subgroups: IR6h 、IR1d、IR2d、IR3d;LI6h、LI1d、LI2d、LI3d. Lithium was injected into LI-group’s abdominal cavity one hour after ischemia, and once everyday until they were killed. Saline was injected into IR-group’s with the same treatment. P-Akt protein levels in ischemia hippocampus were detected by Western Blotting. Result ①in Experiment 1, compared to other dosage groups, by 2-day postinsult treatment with lithium, the levels of P-Akt of 3-mmol-per-kg-dosage group were highest; ②in Experiment 2, P-Akt was detectable 6 hours after ischemia in both groups, and the levels of P-Akt expression reached the highest 3 days later. Within the same period, P-Akt was up-regulated more action in LI group than that in IR group. Conclusion our results suggest that postinsult lithium treatment increases the levels of anti-apoptotic protein P-Akt, and it is appropriate with 3mmol/kg.
