The amygdala is the central component of a functional brain system regulating fear and emotional behaviors. Studies of the ontogeny of fear behaviors reveal the emergence of distinct fear responses at different postnatal ages. Here, we performed a stereological analysis of the rat amygdala to characterize the cellular changes underlying its normal structural development. Distinct amygdala nucle...

Background and Purpose The therapeutic effects of fluoxetine are believed to be due increasing neuronal plasticity reversing some learning deficits. Nevertheless, a growing amount evidence shows adverse this drug on cognition forms plasticity. Experimental Approach To study the chronic treatment, we combine an automated assessment motivation in mice with investigation central amygdala basolater...

The central ghrelin signaling system engages key pathways of importance for feeding control, recently shown to include those engaged in anxiety-like behavior in rodents. Here we sought to determine whether ghrelin impacts on the central serotonin system, which has an important role in anxiety. We focused on two brain areas, the amygdala (of importance for the mediation of fear and anxiety) and ...

Anxiety is integrated in the amygdaloid nuclei and involves the interplay of the amygdala and various other areas of the brain. Neuropeptides play a critical role in regulating this process. Neuropeptide Y (NPY), a 36 aa peptide, is highly expressed in the amygdala. It exerts potent anxiolytic effects through cognate postsynaptic Y1 receptors, but augments anxiety through presynaptic Y2 recepto...

In recent years, the amygdala has emerged as a critical site of plasticity for the acquisition of various forms of Pavlovian learning, either aversive or appetitive. In most of these models, the critical site of plasticity has been localized to the basolateral complex of the amygdala (BLA). In contrast, the central nucleus of the amygdala has emerged as a passive relay of potentiated BLA output...

Introduction: There are many similarities between memory impairment in patients suffering from Alzheimer and animals treated by Cannabinoids. The agonists of Cannabinoid receptors affect on a variety of memories and leanings. The present study aims to investigate the role of α-1-adrenergic receptors in central region of amygdala in state-dependent learning induced by WIN55,212-2 (cannabinoid ag...

There is strong evidence that two cerebral hemispheres are differentially involved in emotional memory and that amygdala is a key subcortical structure for emotional experience. The present research investigated the possible involvement of lateralization of basolateral amygdala (BLA) and central amygdala (CEA) in place avoidance memory. For this purpose, male Long-Evans rats (280-320 g) were im...

gamma-Aminobutyric acid (GABA) is the primary inhibitory transmitter in the mammalian brain. This inhibition is mediated by type A (GABA(A)) receptors that are pentameric proteins assembled from 14 different subunits. Although inhibitory synaptic transmission has been studied in the amygdala, the subunit composition of receptors present at different synapses is not well understood. In this stud...

The amygdala is a limbic brain region that plays a key role in emotional processing, neuropsychiatric disorders, and the emotional-affective dimension of pain. Preclinical and clinical studies have identified amygdala hyperactivity as well as impairment of cortical control mechanisms in pain states. Hyperactivity of basolateral amygdala (BLA) neurons generates enhanced feedforward inhibition an...