Mechanisms involved in memory processes: Alterations induced by psychostimulants - Targeting the central AT1 receptors

Abstract

Learned experiences are indispensable for adaptation and survival ofeveryliving organism. The generation of a memory trace is an activephysiological process which implies association and organization of thenew impressions with already stored ones. Therefore, memory is explainedas activity-dependent synaptic plasticity, involving electrophysiological,biochemical and morphological changes in functional synapse.Throughout the different stages of information processing, emotionand memories interact to shape data encoding and retrieval. Dopamineplays a key role in the control of mood, fear and anxiety, and modulatesthe biochemical processes of memory. Hence, more plastic and appropriateresponses can be achieved to variable external demands.Among drugs of abuse worldwide consumed, psychostimulants areknown for their stimulant properties within the central nervous system.Monoaminergic neurotransmission elicited by amphetamine alters neuronalconnectivity in several brain areas; thus, its pharmacological actionscan be extended to learning and memory processes. Evidence indicates acomplex scenario after psychostimulant administration where long-termmemory can be either impaired or enhanced, according to the experimentalconditions.