NITRIC-OXIDE AGONIST STIMULATES CONSOLIDATION OF LONG-TERM-MEMORY IN THE 1-DAY-OLD CHICK

Chicks, age 1 to 2 days, that have been trained on a passive avoidance task with a strongly reinforced training trial yield a memory trace t hat is composed of 3 behaviorally and pharmacologically distinguishabl e stages, with the final long-term memory stage being dependent on pro tein synthesis. In contrast, chicks trained with a weakly reinforced l earning trial typically do net demonstrate this final stage of memory. Sodium nitroprusside 150 mu M intracranially administered immediately after a weak training trial promoted the formation of long-term memor y, whereas saline did not. The results suggest that nitric oxide synth esis is either itself critical or stimulates other processes that art critical for the consolidation of long-term memory.