Ultrastructural characterization of noradrenergic- and beta-adrenergic receptor-containing profiles in the lateral nucleus of the amygdala
Norepinephrine (NE) is thought to play a key role in fear and anxiety, but its role in amygdala-dependent Pavlovian fear conditioning, a major model for understanding the neural basis of fear, is poorly understood. The lateral nucleus of the amygdala (LA) is a critical brain region for fear learning...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2010-10-01
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| Series: | Frontiers in Behavioral Neuroscience |
| Subjects: | |
| Online Access: | http://journal.frontiersin.org/Journal/10.3389/fnbeh.2010.00162/full |
| _version_ | 1818367823529902080 |
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| author | Claudia Farb William Chang Joseph LeDoux Joseph LeDoux |
| author_facet | Claudia Farb William Chang Joseph LeDoux Joseph LeDoux |
| author_sort | Claudia Farb |
| collection | DOAJ |
| description | Norepinephrine (NE) is thought to play a key role in fear and anxiety, but its role in amygdala-dependent Pavlovian fear conditioning, a major model for understanding the neural basis of fear, is poorly understood. The lateral nucleus of the amygdala (LA) is a critical brain region for fear learning and regulating the effects of stress on memory. To understand better the cellular mechanisms of NE and its adrenergic receptors in the LA, we used antibodies directed against dopamine beta-hydroxylase (DβH), the synthetic enzyme for NE, or against two different isoforms of the beta-adrenergic receptors (βARs), one that predominately recognizes neurons (βAR 248) and the other astrocytes (βAR 404), to characterize the microenvironments of DβH and βAR. By electron microscopy, most DβH terminals did not make synapses, but when they did, they formed both asymmetric and symmetric synapses. By light microscopy, βARs were present in both neurons and astrocytes. Confocal microscopy revealed that both excitatory and inhibitory neurons express βAR248. By electron microscopy, βAR 248 was present in neuronal cell bodies, dendritic shafts and spines, and some axon terminals and astrocytes. When in dendrites and spines, βAR 248 was frequently concentrated along plasma membranes and at post-synaptic densities of asymmetric (excitatory) synapses. βAR 404 was expressed predominately in astrocytic cell bodies and processes. These astrocytic processes were frequently interposed between unlabeled terminals or ensheathed asymmetric synapses. Our findings provide a morphological basis for understanding ways in which NE may modulate transmission by acting via synaptic or non-synaptic mechanisms in the LA. |
| first_indexed | 2024-12-13T22:58:11Z |
| format | Article |
| id | doaj.art-59ec191d10714b4fa7aa78feea9753e5 |
| institution | Directory Open Access Journal |
| issn | 1662-5153 |
| language | English |
| last_indexed | 2024-12-13T22:58:11Z |
| publishDate | 2010-10-01 |
| publisher | Frontiers Media S.A. |
| record_format | Article |
| series | Frontiers in Behavioral Neuroscience |
| spelling | doaj.art-59ec191d10714b4fa7aa78feea9753e52022-12-21T23:28:28ZengFrontiers Media S.A.Frontiers in Behavioral Neuroscience1662-51532010-10-01410.3389/fnbeh.2010.001621983Ultrastructural characterization of noradrenergic- and beta-adrenergic receptor-containing profiles in the lateral nucleus of the amygdalaClaudia Farb0William Chang1Joseph LeDoux2Joseph LeDoux3NYUNYUNYUNathan Kline InstituteNorepinephrine (NE) is thought to play a key role in fear and anxiety, but its role in amygdala-dependent Pavlovian fear conditioning, a major model for understanding the neural basis of fear, is poorly understood. The lateral nucleus of the amygdala (LA) is a critical brain region for fear learning and regulating the effects of stress on memory. To understand better the cellular mechanisms of NE and its adrenergic receptors in the LA, we used antibodies directed against dopamine beta-hydroxylase (DβH), the synthetic enzyme for NE, or against two different isoforms of the beta-adrenergic receptors (βARs), one that predominately recognizes neurons (βAR 248) and the other astrocytes (βAR 404), to characterize the microenvironments of DβH and βAR. By electron microscopy, most DβH terminals did not make synapses, but when they did, they formed both asymmetric and symmetric synapses. By light microscopy, βARs were present in both neurons and astrocytes. Confocal microscopy revealed that both excitatory and inhibitory neurons express βAR248. By electron microscopy, βAR 248 was present in neuronal cell bodies, dendritic shafts and spines, and some axon terminals and astrocytes. When in dendrites and spines, βAR 248 was frequently concentrated along plasma membranes and at post-synaptic densities of asymmetric (excitatory) synapses. βAR 404 was expressed predominately in astrocytic cell bodies and processes. These astrocytic processes were frequently interposed between unlabeled terminals or ensheathed asymmetric synapses. Our findings provide a morphological basis for understanding ways in which NE may modulate transmission by acting via synaptic or non-synaptic mechanisms in the LA.http://journal.frontiersin.org/Journal/10.3389/fnbeh.2010.00162/fullFearNorepinephrinevolume transmissionastrocytesynapseElectron microscopy |
| spellingShingle | Claudia Farb William Chang Joseph LeDoux Joseph LeDoux Ultrastructural characterization of noradrenergic- and beta-adrenergic receptor-containing profiles in the lateral nucleus of the amygdala Frontiers in Behavioral Neuroscience Fear Norepinephrine volume transmission astrocyte synapse Electron microscopy |
| title | Ultrastructural characterization of noradrenergic- and beta-adrenergic receptor-containing profiles in the lateral nucleus of the amygdala |
| title_full | Ultrastructural characterization of noradrenergic- and beta-adrenergic receptor-containing profiles in the lateral nucleus of the amygdala |
| title_fullStr | Ultrastructural characterization of noradrenergic- and beta-adrenergic receptor-containing profiles in the lateral nucleus of the amygdala |
| title_full_unstemmed | Ultrastructural characterization of noradrenergic- and beta-adrenergic receptor-containing profiles in the lateral nucleus of the amygdala |
| title_short | Ultrastructural characterization of noradrenergic- and beta-adrenergic receptor-containing profiles in the lateral nucleus of the amygdala |
| title_sort | ultrastructural characterization of noradrenergic and beta adrenergic receptor containing profiles in the lateral nucleus of the amygdala |
| topic | Fear Norepinephrine volume transmission astrocyte synapse Electron microscopy |
| url | http://journal.frontiersin.org/Journal/10.3389/fnbeh.2010.00162/full |
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