Post-Exposure Exercise Fails to Ameliorate Memory Impairment Induced by Propofol and Ketamine in Developing Rats

BACKGROUND: This aim of this study was to determine the effects of ketamine-propofol combination on learning and memory, as well as exercise, on anesthetic neurotoxicity. MATERIAL/METHODS: A ketamine-propofol combination was administered once (group SKP, Single Ketamine Propofol) on P7 (postnatal day 7) or in 3 treatments on P6, P8, and P10 (group MKP, Multiple Ketamine Propofol). Rat pups in group C (Control) received equivalent volumes of normal saline in 3 injections on P6, P8, and P10. Rats designated MKPR (Multiple Ketamine Propofol and running) and CR (Control and running) began running exercise on P21 on wheels. Learning and memory was assessed by Morris water maze and fear conditioning tests. Hippocampal neurogenesis of rats was detected by BrdU immunofluorescence. RESULTS: MKP rats had longer latency to platform than group C during training in the Morris water maze; SKP rats stayed in the target quadrant longer than MKP rats during testing (P<0.05). Rats in running groups had shorter latency than non-running rats, but running had no interaction with anesthesia exposure. CONCLUSIONS: Repeat ketamine-propofol combination doses increase risk of memory impairment in developing rats. Running has no impact on anesthetic neurotoxicity.