ABSTRACT
Objective To investigate the expression of NMDAR1 in the hippocampus and cerebral cortex of old rats after 30-min -inhalation of 2% isoflurane, and to investigate the effects of isoflurane on the learning and memory functions of old rats and the underlying mechanism. Methods The healthy old male Sprague Dawley rats (n = 36) were randomly divided into the control group, the oxygen group, the 2-hour post-recovery group, the 1-day post-recovery group, the 3-day post-recovery group, and the 7-day post-recovery group. The morris water maze was used to detect the ethological effect of 30-min inhalation of isoflurane , and the immunohistochemistry assay was used to detect the expression of NMDAR1 in the hippocampus (CA1, CA3) and the cerebral cortex. Results The 30-min inhalation of 2% isoflurane inhibited the learning and memory abilities of old rats at 2 h post-recovery. On 1 d post-recovery, the inhibition of learning and memory began to reduce, then on 3 d and 7 d post-recovery, the learning and memory abilities continously recovered. The expression of NMDAR1 in the rat hippocampus and cerebral cortex decreased at 2 h post-recovery, and reversed on 1 d post-recovery and reached the normal level on 3 d and 7 d post-recovery. Conclusion 30-min inhalation of 2%isoflurane had an inhibitory effect on the learning and memory abilities of old rats, and the attenuation of NMDAR1 in the hippocampus and cerebral cortex may involve in this process.