Effect of propofol anesthesia on autophagy in hippocampal neurons of newborn rats / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the effect of propofol anesthesia on autophagy in hippocampal neurons of newborn rats.Methods:Thirty-nine healthy Sprague-Dawley rats, aged 7 days, weighing 10-12 g, were divided into 3 groups ( n=13 each) using a random number table method: control group (group C), fat emulsion group (group F) and propofol group (group P). Normal saline 8 ml/kg was intraperitoneally injected for 5 consecutive days in group C. Medium-/long-chain fatty emulsion injection 8 ml/kg was intraperitoneally injected for 5 consecutive days in group F. Medium-/long-chain propofol injection 80 mg/kg was intraperitoneally injected for 5 consecutive days in group P. Five rats were sacrificed on 1st day after the end of propofol anesthesia, and hippocampal tissues were taken for determination of the expression of microtubule-associated protein 1 light chain 3B (LC3B) and Beclin-1 (by Western blot). The remaining rats in each group underwent the Morris water maze test on 19th day after the end of propofol anesthesia (30 days after birth), and the escape latency, percentage of time of staying at the target quadrant and the number of crossing the original platform were recorded. Results:Compared with group C, no significant change was found in the expression of hippocampal LC3B and Beclin-1, escape latency, percentage of time of staying at the target quadrant, and the number of crossing the original platform in group F ( P>0.05), and the expression of hippocampal LC3B and Beclin-1 was significantly up-regulated, the escape latency was prolonged, percentage of time of staying at the target quadrant was decreased, and the number of crossing the original platform was decreased in group P ( P<0.05 or 0.01). Conclusion:The mechanism by which propofol anesthesia causes long-term cognitive dysfunction may be related to promoting autophagy in hippocampal neurons of newborn rats.