Although a number of signal transduction pathways have been implicated in short- and long-term adaptative changes in neuronal plasticity and memory formation, there is increasing evidence that cross-talk between the cAMP- and Ca2+-regulatory pathways may play a pivotal role in learning and...

Histamine is an important but largely neglected modulator in the central nervous sys- tem. Histaminergic neurons are located exclusively in the posterior hypothalamus, the tuberomammillary nucleus (TM), from where they project to almost all brain regions, with ventral areas (hypothalamus,...

How long-term memories are formed in the brain is one of the principal targets of contemporary neuroscience research. This work is important from a fundamental perspective, because memory is a vital component of virtually all cognitive activity. It is also important from a clinical...

The serotonergic system is widely distributed in the central nervous system and plays a role in many behavioral and physiological processes. However, converging data indi cate that serotonin (5-HT) is specifically involved in learning and memory by interacting with major neurotransmitters....

This chapter reviews the involvement of PKC in cognition and in the brain pathologies affecting cognition. PKC is a family of enzymes. Its activation process is described in the first part. In the second part, we analyse the role of PKC in synaptic plasticity, a neuronal property which may...

Evidence implicating protein serine/threonine phosphorylation in memory formation and related brain processes continues to accumulate at a rapid rate. Several protein kinases have been demonstrated to play critical roles in models of synaptic plasticity, such as long-term potentiation, and also...

Ca2+ plays an essential role in a variety of intracellular signaling cascades, which under- lie mechanisms essential for the dynamic control of cell functions. In cognition, Ca2+ participates in control of not only the formation and development of neural structures that cognition depends on,...

To date, numerous publications have reported on the effects of opioids in learning and memory, and much research has been conducted on novel opioid receptor ligands as anti-amnesic drugs. The involvement of the opioid system including opioid peptides and their receptors has been increasingly...

Since the discovery that dopamine occurs in the cerebral cortex and functions as a trans mitter a large number of studies has been conducted to examine its precise functions. It was found that administering dopaminergic drugs, either stimulating or inhibiting dopamine receptors, affected...

Potassium-selective channels are ubiquitous constituents of plasma membranes, and are structurally and physiologically diverse. It is considered that their multiplicity of form allows for the fine-tuning of membrane responses to changes in potential or intracellular environment. In neurons,...

Glutamate as a neurotransmitter plays a critical role in multiple processes in the brain from early development to ageing and includes important functions in memory formation. Both ionotropic and metabotropic glutamate receptors are involved in these functions but a close review assessing the...

In this chapter studies are considered concerning the actions of GABAA and GABAB receptor agonists and antagonists on memory formation in laboratory animals. Peripheral posttraining administrations of GABAergic drugs produce time- and dose-dependent effects on memory in animals tested in a...

The study of brain muscarinic receptors began more than a century ago, long before the existence of muscarinic receptors was postulated and then demonstrated. However, the effects of drugs acting on these receptors, such as atropine, eserine, pilocarpine and arecoline had been studied much...

The nicotinic cholinergic system has been widely implicated in mediating learning and/or memory processes in human and nonhuman animals. This chapter highlights various areas of basic research in which stimulation or blockade of nicotinic acetylcholine receptors (nAChRs) has been shown to...

Noradrenaline released in the brain can potentially act on any of 9 different receptor subtypes and since activation of the different receptors produces quite different effects both in duration and time-course of memory, noradrenaline can produce very complicated behavioral responses. Using a...

Adenosine can act on four subtypes of receptor, of which the A1 and A2A subtypes have received the most attention experimentally. The A1 receptors are primarily inhibitory by depressing transmitter release or causing hyperpolarisation, while the A2A receptors often cause overall excitation by...

Despite its long tradition in human psychopharmacology, animal studies on the effect of marijuana and its constituents in memory formation are relatively recent. They have been aided by both the development of synthetic cannabinoid drugs and the identification of specific receptors located in...

Neuropeptides are peptides involved in nervous system function. They are synthesized in cells in large precursor proteins, and generally several biologically active peptides are contained in the same precursor molecule. Various biochemical processes control the quantities of neuropeptides, as...

Cell division, cell death, and cell differentiation are hallmarks of embryogenesis. Such processes are supported by neurotrophins that have the capacity of regulating not only developmental processes, but also neuronal survival, morphological adaptation, and neural plasticity. Nerve growth...

Glucocorticoid hormones, released from the adrenal glands, easily access the brain where they can affect neural structure and function through the binding to two types of intracellular receptors, the mineralocorticoid receptor (MR) and the glucocorticoid receptor (GR). Secretion of these...

Memory formation is dependent on a series of biochemical cascades that alter synaptic transmission and neuronal activity. Phospholipases are key enzymes in these cascades that produce second messengers, which interact with a host of target systems, such as transmitter uptake systems,...

Memories are believed to rely upon enduring morphologic and functional changes at synapses activated by learning events. Experiments carried out in the past two decades have indicated that several cellular mechanisms need to be activated in order for the synaptic changes to take place. Among...

The modification of synaptic properties by means of protein phosphorylation has been, for long, recognized as a core and unifying principle in the study of the molecular mechanisms underlying the formation and storage of new memories. The intrinsically transient nature of this...

In neurons the extracellular-signal-regulated kinases (ERKs) are emerging as important regulators of neuronal function. This chapter will discuss the great progress that has been made in identifying the essential components of the signal transduction pathways that lead to ERK activation and...

Among three isoforms of nitric oxide (NO) synthase, both neuronal and endothelial NO synthases may play an important role in learning and memory. NO production in the brain increases, in an activity-dependent manner, following an increase in intracellular Ca2+ levels. Electrophysiological...

The cAMP Responsive Element Binding Protein (CREB) is an activity regulated transcription factor that modulates the transcription of genes with cAMP responsive elements (CRE) located in their promoter regions. A variety of signaling pathways converge to phosphorylate CREB at Ser133 and induce...

The formation of long-lasting memory traces depends on the de novo synthesis of proteins. For more than 30 years substantial experimental evidence has been collected in species ranging from insects to mammals, in support of this hypothesis. A pharmacological approach to investigate the...

The role of protein synthesis in long-term memory formation is still an area of intense scientific interest, which encompasses the study of mechanisms involved in gene expression and molecular mechanisms underlying synaptic plasticity. A number of low molecular weight compounds have been used...

This chapter analyzes the results of quantitative electron microscopic studies of the vertebrate brain aimed at the elucidation of changes in synaptic unltrastructure that may underlie learning and memory. It has been reported that behavioral learning promotes new synapse formation, including...

The net effect of an experimentally-induced or “naturally” occurring alteration in learning and memory is generally determined by the type of neurological dysfunction (from focal lesions to gene expression) and/or the nature of the learning task. Accordingly, memory systems are defined as...

Normal brain aging is associated with physiological alterations in Ca2+ homeostasis and deficits in learning and memory. The hippocampus, a structure critical for proper learning and memory functions, is frequently implicated in aging-related learning deficits. Consistent with the “Ca2+...

Eph receptor tyrosine kinases are largely known for their involvement in brain development. But, as these receptors are also expressed in the adult, their possible role in the mature nervous system has begun to be explored. Emerging evidence for the involvement of Eph receptors in synaptic...

The molecular cascade of events associated with hippocampal processing of information for long-term storage is a time-limited event. Learning sets in motion neural processes that continue to evolve after training, a phenomenon known as consolidation. The consolidation process has been proposed...

Destruction of muscle fibres accompanied by a reactive regenerative response is a major defining characteristic that distinguishes the muscular dystrophies from the more general category of myopathies caused by genetic defects that impact on skeletal muscle.1 In the early stages of severe...