Cycloheximide affects Memory within Minutes after the Onset of Training

Abstract

WHEN mice are given brief discrimination training in a T-maze following intracerebral or subcutaneous administration of the protein synthesis inhibitors cycloheximide or acetoxycyclo-heximide, their learning curves are indistinguishable from saline-injected controls^1,2. Retention measured 3 h after training is also identical in the drug-treated and control groups, but 6 h after training the drug-treated mice exhibit a striking impairment of retention^1,2. These results suggested that cerebral protein synthesis is not required for retention for at least 3 h after training. We now report that using an alternative training procedure a cycloheximide-sensitive component of memory storage can be detected within minutes after the beginning of training. This suggests that in some circumstances cerebral protein synthesis may be required for normal expression of memory within minutes after learning has begun.