No abstract

No abstract

Subcutaneous injection of 240 micrograms of acetoxycycloheximide in mice rapidly produces marked inhibition of cerebral protein synthesis. Treated mice were trained to escape shock by choosing the lighted limb of a T-maze. When trained five or more minutes after injection, they had a normal capacity to learn. They remembered normally 3 hours after training, but 6 hours after training they had markedly impaired retention. Amnesia persisted thereafter. Injections immediately after training had a less marked but significant amnesic effect. These studies suggest that protein synthesis is not necessary for learning or for memory for 3 hours after training but that it is required for long-term memory. The protein synthesis which appears to be necessary for long-term e3memory occurs during training, or within minutes after training, or both.

Mice injected bitemporally with puromycin 5 hours before training learned to escape or to avoid shock by choosing the correct limb of a Y-maze. When retested 15 minutes after training they had normal retention. In the ensuing 2(3/4) hours the animals injected with puromycin, unlike the controls, showed a progressive decrease of savings to less than 7 percent.