Effect of propofol combined with sevoflurane anesthesia on GABA A receptor α 1/α 2 subunit homeostasis in hippocampus of rats with mild cognitive impairment / 中华麻醉学杂志

ABSTRACT

Objective:To evaluate the effect of propofol combined with sevoflurane anesthesia on GABA A receptor (GABA AR)α 1/α 2 subunit homeostasis in hippocampus of rats with mild cognitive impairment (MCI). Methods:Healthy clean-grade male Sprague-Dawley rats, aged 16-18 months, weighing 450-550 g, were anesthetized.MCI was induced by ligation of bilateral common carotid arteries after anesthesia.Morris water maze test was used to select the rats with MCI at 30 days after establishment of the model.The rats with MCI were divided into 4 groups ( n=18 each) using a random number table method: sham operation group (group Sham), sevoflurane anesthesia group (group S), propofol anesthesia group (group P), and propofol combined with sevoflurane anesthesia group (group SP). The rats inhaled 3% sevoflurane for 3 h in group S. Propofol 40 mg·kg -1·h -1 was intravenously infused for 3 h in group P. The rats inhaled 1.7% sevoflurane, and propofol 20 mg·kg -1·h -1 was intravenously infused for 3 h simultaneously in group SP.Open reduction and internal fixation was performed after tibial fracture was induced in S, P and SP groups.Y-maze test was performed at 14 days after operation to assess cognitive function.The expression of potassium-chloride cotransporter-2 (KCC2), sodium-potassium-chloride cotransporter 1 (NKCC1), GABA ARα 1 and GABA ARα 2 was determined using Western blot. Results:Compared with group Sham, the percentage of time of staying at novel arm was significantly decreased, the expression of hippocampal KCC2 and GABA ARα 1 was down-regulated, and the expression of NKCC1 and GABA ARα 2 was up-regulated in S and P groups ( P<0.05), and no significant change was found in the parameters mentioned above in group SP ( P>0.05). Compared with group S or group P, the percentage of time of staying at novel arm was significantly increased, the expression of hippocampal KCC2 and GABA ARα 1was up-regulated, and the expression of NKCC1 and GABA ARα 2 was down-regulated in group SP ( P<0.05). Conclusion:The mechanism by which propofol combined with sevoflurane anesthesia does not aggravate the postoperative cognitive dysfunction may be related to maintaining GABA ARα 1/α 2 subunit homeostasis in rats with MCI.