Alterations in high affinity choline accumulation rate in rat cerebral cortex during anaesthesia with ketamine and...

After i.p. injection of ketamine (75 mg/kg) or pentobarbital-Na (40 mg/kg) to rats, there was a rapid, then a steady decrease of the sodium-dependent high affinity choline (HAC) accumulation rate to a minimum. This minimum was followed by a rapid increase (ketamine) or a gradual rise (pentobarbital-Na). Immediately after the rats came out of anaesthesia, the accumulation rate had not yet completely recovered. We suggest the ketamine or pentobarbital-Na induce alterations in central cholinergic systems, i.e. changes in choline uptake and incorporation into acetylcholine. It is conceivable that interactions of cholinesterase inhibitors or corticosteroids with the anaesthetics are based upon some modification of these changes.