Effect Of Ketamine Anesthesia For Neonate On Learning And Memory Of Adult Rats

Objective:To determine sub-anesthetic dose of ketamine for7days old SD rats on the basis of animal experiments and literature search. And to induce long-term potentiation in hippocampus of normal adult rats in vivo.Methods:20SD rats of7days old were used in the first part, half male and half female. They were divided into four groups:group C, K1, K2, K3, which was injected with0.2ml NS or25,50,100mg/kg ketamine (diluted to0.2ml with NS).0.2ml blood was extracted from left ventricular for blood-gas analysis10min later. Body weight of each rat was recorded for three days.6adult SD rats were used in the other part. After being anesthetized with20%Urethane, each rat was fixed in stereotaxic apparatus and long-term potentiation was induced on hippocampus.Results:After ketamine being injected, rats of group K3appeared respiratory depression quickly. Results of blood-gas analysis were no significant difference among group Kl, K2and C (P>0.05), also as weight (P>0.05). Induction of LTP on hippocampus of normal adult rats was successful and stable.Conclusion:It didn’t affect the result of blood-gas analysis and weight gain those rats of7days old were anesthetized with25mg/kg or50mg/kg ketamine. We could accurately locate the specified region on hippocampus and induce LTP on hippocampus of normal adult rats successfully and stably following our experimental method. Objective: To observe the effect of ketamine of intracerebroventricular inject to adult SD rats on LTP of Hippocampus.Methods:12Adult SD rats, weight about250g, half male and half female. They were randomly divided into group C and group C-I. After being successfully anesthetized by urethane, each rat was fixed on stereotaxic apparatus. LTP was recorded after intracerebroventricular injection of NS or ketamine (50μg)5μl respectively.Results:30min after stimulation, PS amplitudes of group C and C-I were (216.29±12.11)%and (138.04±6.50)%(P<0.05).60min after stimulation, PS amplitudes were (202.33±11.53)%and (149.60±10.86)%(P<0.05). LTP of group C-I reduced obviously.Conclusion:Ketamine of intracerebroventricular injection to adult SD rats can reduce synaptic plasticity of hippocampus. Objective: To observe the effect of single ketamine anesthesia for neonate on MWM and LTP of adult SD rats.Methods:30seven days old SD rats were divided into group C (NS0.2ml, ip.), group K1(ketamine50mg/kg, ip.) and group K0.5(ketamine25mg/kg, ip.). MWM and hippocampal LTP were recorded respectively at rats2.5months old and one week later.Results:In MWM, three groups showed no significant difference (P>0.05). In LTP, group K1and K0.5showed significant lower compared with group C (P<0.05), but no significant difference between them (P>0.05).Conclusion:Single ketamine anesthesia for neonate reduced synaptic plasticity of adult SD rats, but didn’t affect spatial learning and memory. And light and deep anesthesia had the same effect on degree of inhibiton to synaptic plasticity.