Abstract:

Objective To investigate the effect of ketamine on learning and memory function of adult rats after injection of ketamine at early development stage. Methods Twelve rats born in a week were randomly divided into ketamine anesthesia group (Ket group) and normal saline control group (Ns group). Rats in Ket group were intraperitoneally injected with 50 mg/kg ketamine, and those in Ns group were administrated with same amount of normal saline. After eight weeks, Morris water maze test was adopted to explore the latency in place navigation and spatial probe ability. The sections of hippocampus were obtained, and immunohistochemical staining was employed to detect the expression of Bax and Bcl-2. Results In Morris water maze test, the latency in place navigation of Ket group was significantly longer than that of Ns group (P<0.05), and the spatial probe ability significantly decreased (P<0.05). It was revealed by immunohistochemical staining that the expression of Bax in Ket group was significantly higher than that in Ns group, while there was no significant difference in the expression of Bcl-2 between these two groups. Conclusion Application of ketamine in neonatal rats may result in learning and memory impairment in adulthood, and the underlying mechanism may correlate to the apoptosis of neuron in hippocampus region.

Key words: ketamine, Morris water maze, apoptosis