Effects of lithium chloride pretreatment on cognitive function after laparotomy in aged rats / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effects of lithium chloride pretreatnent on cognitive function after laparotomy in aged rats. Methods Forty-eight male SD rats aged 18 months, weighing 550-700 g were randomly divided into 3 groups (n = 16 each) group Ⅰ control (group C); group Ⅱ operation (group O) and group Ⅲ lithium chloride preconditioning (group L). In group L lithium chloride 2 mmol/kg was injected intraperitoneally (IP) once a day for 7 consecutive days before exploratory laparotomy. In group C and group O equal volume of normal saline was injected instead of lithium chloride. The animals were anesthetized with IP 2 % pentobarbital 0.25 ml/100 g. Morris water-maze (MWM) test was performed at day 4-6 after operation in 8 animals in each group. Another 8 animals were killed at 24 h after operation and their brains were immediately removed for determination of IL-1β content and expression of total glycogen synthase kinase-3β (GSK-3β) and p-GSK-3β in hippocampus by ELISA and Western blot respectively. Results Compared with group C the escape latency and swimming distance were both significantly prolonged at day 4-6 after operation in group O, while in group L only swimming distance was prolonged at day 4 after operation. The IL-1β content in hippocampus was significantly higher and the expression of p-GSK-3β was significantly lower in group O than in group C and L. There was no significant difference in total GSK-3β among the 3 groups. Conclusion Lithium chloride pretreatment can improve the cognitive function after laparotomy in aged rats by inhibiting GSK-3β activity and attenuating inflammatory response in hippocampus.