Learning And Memory-associated Changes Of Endogenous Nitric Oxide In Adult And Aged Animals And Related Signaling Events

Nitric oxide (NO) is a soluble gas that acts as a novel type of intercellular messenger molecule in the central nervous system. NO has been suggested to play a role in learning and memory. While nitric oxide synthase (NOS) inhibitors have previously been shown to impaired the performance of animals in several learning and memory paradigms, NO donor enhanced the memory . However, the involvement of NO in mammalian learning is still controversial. Especially, the changes of endogenous NO during acquisition or retention remains to be determined, and signaling pathway of NO action in learning and memory are poorly understood. In this study, we investigated the changes of NO in the brain related to memory in adult and aged animals, and further investigated its signaling events.Part I changes of endogenous nitric oxide in rat brain related to learning and memory1. The changes of NOS activity in rat brain after a water-rewarded spatial alternation task. Rats were trained in a Y-maze using our previously reported procedure. NOS activity was assayed by conversion by [~3H] L-arginine to [~3H] L-citrulline.