Effects of different doses of remifentanil on short-term learning and memory ability in the developing rats / 临床麻醉学杂志

ABSTRACT

Objective To investigate the effects of different doses of remifentanil on learning and memory ability,the expression of hippocampal tissue phosphorylation of cAMP response element binding protein (p-CREB)in developing rats.Methods A total of 72 Sprague-Dawley rats (1 9-23 g) were randomly divided into 4 groups (n =18 each)Group Cnormal saline control group;R1,R2, R3 group received continuous intraperitoneal remifentanil 1,5,10 μg·kg-1 ·min-1 for 2 hours re-spectively.Both total volume of remifentanil and saline were 2 ml.The SpO 2 and pulse rates were mo-nitored during the experiment.Step-down test was used to evaluate the learning and memory ability, while Western blot analysis was performed to measure the expression of hippocampal p-CREB protein in 4 h,24 h,1 week when the rats were awake.Results Compared with group C,group R1 and R2, pulse rates of group R3 decreased significantly (P <0.05 ),but the changes of SpO 2 in each group were not statistically significant.At 4 h pointcompared with group C and group R1,the error times in step-down test were increased in both group R2 and R3,the latencies were shortened (P <0.05);Compared with group R2,the error times were increased in group R3,latency was shortened (P <0.05).At 24 h point,compared with group C and group R1,the error times were increased in group R2,R3,latencies were shortened (P < 0.05 );Compared with group R2,the error times were in-creased in group R3,latency was shortened (P <0.05 ).The error times and latency of each group had not statistical significance in one week.At 4 h point,the expression of p-CREB protein in hippo-campus of group R3 downregulated compared with group C and group R1,R2,respectively (P <0.05).At 24 h point,the expression of p-CREB protein in hippocampus of group R2,R3 decreased compared with group C and group R1 respectively(P <0.05);The expression of p-CREB protein in each group had no statistical significance in one week.Conclusion 5-10 μg · kg-1 · min-1 dose of remifentanil can result in a decline of learning and memory ability in the developing rats in short-term,and the mechanism may relate to the inhibition of p-CREB protein expression in hippocampus.