Inhibitors of protein synthesis involved in memory disruption. A study of their effects on sympathetic ganglion isolated in vitro

Effect of inhibitors of protein synthesis on dopamine modulation of the slow-EPSP in rabbit superior cervical ganglion

The protein synthesis inhibitors, anisomycin and cycloheximide, were tested for their ability to prevent dopamine-induced long-term enhancement of the slow-EPSP in rabbit superior cervical ganglion. Exposure of ganglia to either inhibitor of protein synthesis, at a concentration that suppressed [3H]leucine incorporation into ganglionic protein by at least 95%, had no effect on the development of dopamine-induced enhancement of the slow-EPSP. Incubation of ganglia with dopamine, without an inhibitor of protein synthesis, was without effect on [3H]leucine incorporation into ganglionic protein. It is concluded that synthesis of new protein is not required for the development of long-term enhancement of the slow-EPSP induced by dopamine.

The effect of memory blocking antibiotics and their analogs on acetylcholinesterase

The ability of antibiotics to inhibit acetylcholinesterase was measured in homogenates of goldfish brain. Puromycin aminonucleoside was the most potent inhibitor followed by puromycin, cycloheximide and acetoxycycloheximide. Puromycin effectively impaired retention of active-avoidance learning in goldfish when injected either immediately before or after training, while puromycin aminonucleoside did not regardless of injection time. These results suggest that the known amnestic effects of puromycin, cycloheximide and acetoxycycloheximide are not a consequence of interference with acetylcholinesterase.