Chemogenetic stimulation of mouse central amygdala corticotropin-releasing factor neurons: Effects on cellular and behavioral correlates of alcohol dependence

AbstractBackgroundCorticotropin-releasing factor (CRF) signaling in the central nucleus of the amygdala (CeA) plays a critical role in rodent models of excessive alcohol drinking. However, the source of CRF acting in the CeA during alcohol withdrawal remains to be identified. In the present study, we hypothesized that CeA CRF interneurons may represent a behaviorally relevant source of CRF to the CeA increasing motivation for alcohol via negative reinforcement.MethodsWe tested this hypothesis in male mice and used chemogenetics to stimulate CeA CRF neurons in vitro and in vivo.ResultsWe first observed that Crh mRNA expression in the anterior part of the mouse CeA, at the junction with the interstitial nucleus of the posterior limb of the anterior commissure, correlates positively with alcohol intake in C57BL/6J males with a history of chronic binge drinking. We then found that chemogenetic activation of CeA CRF neurons in Crh-IRES-Cre mouse brain slices increases gamma-aminobutyric acid (GABA) release in the medial CeA in part via CRF1 receptor activation, indicating local CRF release. While chemogenetic stimulation of CeA CRF neurons exacerbated novelty-induced feeding suppression, as seen in C57BL/6J males withdrawn from chronic intermittent alcohol inhalation, it had no effect on voluntary alcohol consumption, following either acute or chronic manipulation.ConclusionsAltogether, these findings indicate that hyperactivity of CeA CRF neurons may contribute to elevated CeA GABA levels and negative affect during alcohol withdrawal but is not sufficient to drive alcohol intake escalation in dependent mice.

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Factors from paraventricular nucleus mediating adrenocorticotropin release in cats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1987.252.1.r109 ◽

1987 ◽

Vol 252 (1) ◽

pp. R109-R121

Author(s):

D. E. Carlson ◽

D. S. Gann

Keyword(s):

Paraventricular Nucleus ◽

Corticotropin Releasing Factor ◽

Rabbit Serum ◽

Normal Rabbit Serum ◽

Immunocytochemical Localization ◽

Before And After ◽

Alpha Chloralose ◽

Crf Neurons ◽

Caudal Area ◽

Stimulation Of

Experiments were conducted in alpha-chloralose-urethan-anesthetized cats. We stimulated the hypothalamic paraventricular nucleus (PVH) electrically before and after intracerebroventricular (icv) injection of an antiserum to arginine vasopressin (AVP), one to corticotropin-releasing factor (CRF), or one to normal rabbit serum (NRS). Stimulation of the ventral portion of the dorsal PVH led to increases in arterial pressure and heart rate that did not change after any of the icv treatments. However, the effect of each agent on the increases in plasma adrenocorticotropin (ACTH) after stimulation was related to the area of the PVH that was stimulated. The response to stimulation of a rostral area that extended dorsally from the anterior PVH was blocked completely by the anti-AVP but not by anti-CRF or NRS. The response to stimulation of a caudal area located in the dorsal PVH was attenuated after anti-CRF, unchanged after anti-AVP, and augmented after NRS. The antibodies that were given icv were found immunocytochemically to enter the median eminence at sites that include some adjacent to the portal vessels. Immunocytochemical localization of AVP- and of CRF-containing neurons in the PVH showed that the anterior PVH had the highest proportion of AVP neurons in the PVH but had only a few CRF neurons. In contrast, the dorsal PVH contained the highest density of CRF neurons in the PVH as well as some AVP neurons. We suggest that, in the cat, the primary releasing factor for the anterior PVH is AVP and that for the dorsal PVH is CRF.

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Anxiety Reduction and Maternal Aggression in Postpartum Nonhuman Mammals

The Parental Brain ◽

10.1093/oso/9780190848675.003.0006 ◽

2020 ◽

pp. 164-193

Author(s):

Michael Numan

Keyword(s):

Neural Circuitry ◽

Corticotropin Releasing Factor ◽

Anxiety Reduction ◽

Central Nucleus ◽

Ventromedial Nucleus ◽

Stria Terminalis ◽

Maternal Aggression ◽

Postpartum Anxiety ◽

Bed Nucleus ◽

Crf Neurons

Chapter 6 explores the neural mechanisms that regulate the decrease in anxiety and increase in maternal aggression that co-occur in postpartum mammals. Too much anxiety antagonizes maternal aggression. Therefore, postpartum anxiety reduction promotes maternal aggression. The neural circuitry of maternal aggression includes projections from the ventromedial nucleus of the hypothalamus to the periaqueductal gray and to other brainstem sites. Anxiety-related behaviors are mediated by corticotropin-releasing factor (CRF) neurons, and the projection of central nucleus of amygdala (CeA) CRF neurons to the dorsal bed nucleus of the stria terminalis is involved. Neural circuits are described to show how enhanced CRF release can depress maternal aggression. These circuits are typically downregulated in postpartum females, and oxytocin (OT) is involved. OT exerts anxiolytic effects and one mechanism of OT action is to depress the output of CeA.

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Pre- and Postsynaptic Serotoninergic Excitation of Globus Pallidus Neurons

Journal of Neurophysiology ◽

10.1152/jn.00845.2007 ◽

2008 ◽

Vol 100 (2) ◽

pp. 1053-1066 ◽

Cited By ~ 18

Author(s):

Moshe Rav-Acha ◽

Hagai Bergman ◽

Yosef Yarom

Keyword(s):

Basal Ganglia ◽

Firing Rate ◽

Globus Pallidus ◽

Critical Role ◽

Brain Slices ◽

Afferent Input ◽

Central Nucleus ◽

Intracellular Recordings ◽

Current Clamp ◽

Acid Release

The basal ganglia (BG) play a critical role in the pathogenesis and pathophysiology of Parkinson's disease (PD). Recent studies indicate that serotoninergic systems modulate BG activity and may be implicated in the pathophysiology and treatment of PD. The globus pallidus (GP), the rodent homologue of the primate GPe, is the main central nucleus of the basal ganglia, affecting the striatum, the subthalamic nucleus (STN), and BG output structures. We therefore studied the effect of serotonin (5-HT) and specific 5-HT agonists and antagonists on GP neurons from rat brain slices. Using intra- and extracellular recordings of GP neurons we found that serotonin increases the firing rate of GP neurons. Analyzing the effects of specific 5-HT agonists and antagonists on the firing rate of GP neurons showed that the increase in firing rate is due to the activation of 5-HT1B and 5-HT1A receptors. Intracellular recordings in both voltage- and current-clamp modes revealed that serotonin mediates its effect via pre- and postsynaptic mechanisms. The presynaptic effect is mediated by attenuation of γ-aminobutyric acid release, probably through activation of 5-HT1B receptors. Postsynaptically, serotonin activates a hyperpolarization-activated cation channel, probably via 5-HT1A receptors. Furthermore, serotonin decreases the fast synaptic depression characteristic of the striatal afferent input. The decreased serotonin concentrations in the BG nuclei in PD may contribute to depressed GP activity and enhance the emergence of BG pathological synchronous oscillations. We therefore suggest that future therapeutics of PD should be directed toward restoration of normal serotonin levels in BG nuclei.

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Imaging Striatal Dopamine Release Using a Non-Genetically Encoded Near-Infrared Fluorescent Catecholamine Nanosensor

10.1101/356543 ◽

2018 ◽

Cited By ~ 7

Author(s):

Abraham G. Beyene ◽

Kristen Delevich ◽

Jackson Travis Del Bonis-O’Donnell ◽

David J. Piekarski ◽

Wan Chen Lin ◽

...

Keyword(s):

Brain Tissue ◽

Near Infrared ◽

Critical Role ◽

Brain Slices ◽

Biological Tissues ◽

Single Wall Carbon Nanotubes ◽

Fluorescence Signal ◽

Optogenetic Stimulation ◽

Optical Tools ◽

Stimulation Of

AbstractNeuromodulation plays a critical role in brain function in both health and disease. New optical tools, and their validation in biological tissues, are needed that can image neuromodulation with high spatial and temporal resolution, which will add an important new dimension of information to neuroscience research. Here, we demonstrate the use of a catecholamine nanosensor with fluorescent emission in the 1000-1300 nm near-infrared window to measure dopamine transmission in ex vivo brain slices. These near-infrared catecholamine nanosensors (nIRCats) represent a broader class of nanosensors that can be synthesized from non-covalent conjugation of single wall carbon nanotubes (SWNT) with single strand oligonucleotides. We show that nIRCats can be used to detect catecholamine efflux in brain tissue driven by both electrical stimulation or optogenetic stimulation. Spatial analysis of electrically-evoked signals revealed dynamic regions of interest approximately 2 microns in size in which transients scaled with simulation intensity. Optogenetic stimulation of dopaminergic terminals produced similar transients, whereas optogenetic stimulation of glutamatergic terminals showed no effect on nIRCat signal. Bath application of nomifensine prolonged nIRCat fluorescence signal, consistent with reuptake blockade of dopamine. We further show that the chemically synthetic molecular recognition elements of nIRCats permit measurement of dopamine dynamics in the presence of dopamine receptor agonists and antagonists. These nIRCat nanosensors may be advantageous for future use because i) they do not require virus delivery, gene delivery, or protein expression, ii) their near-infrared fluorescence facilitates imaging in optically scattering brain tissue and is compatible for use in conjunction with other optical neuroscience tool sets, iii) the broad availability of unique near-infrared colors have the potential for simultaneous detection of multiple neurochemical signals, and iv) they are compatible with pharmacology. Together, these data suggest nIRCats and other nanosensors of this class can serve as versatile new optical tools to report dynamics of extracellular neuromodulation in the brain.

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Effects of Interleukin-1β in Glycinergic Transmission at the Central Amygdala

Frontiers in Pharmacology ◽

10.3389/fphar.2021.613105 ◽

2021 ◽

Vol 12 ◽

Author(s):

Jocelyn Solorza ◽

Carolina A. Oliva ◽

Karen Castillo ◽

Gabriela Amestica ◽

María Constanza Maldifassi ◽

...

Keyword(s):

Learning And Memory ◽

Inhibitory Activity ◽

Critical Role ◽

Brain Slices ◽

Site Directed Mutagenesis ◽

Interleukin 1Β ◽

Central Nucleus ◽

Central Processing ◽

The Brain ◽

Glycinergic Neurotransmission

Interleukin-1β (IL-1β) is an important cytokine that modulates peripheral and central pain sensitization at the spinal level. Among its effects, it increases spinal cord excitability by reducing inhibitory Glycinergic and GABAergic neurotransmission. In the brain, IL-1β is released by glial cells in regions associated with pain processing during neuropathic pain. It also has important roles in neuroinflammation and in regulating NMDA receptor activity required for learning and memory. The modulation of glycine-mediated inhibitory activity via IL-1β may play a critical role in the perception of different levels of pain. The central nucleus of the amygdala (CeA) participates in receiving and processing pain information. Interestingly, this nucleus is enriched in the regulatory auxiliary glycine receptor (GlyR) β subunit (βGlyR); however, no studies have evaluated the effect of IL-1β on glycinergic neurotransmission in the brain. Hence, we hypothesized that IL-1β may modulate GlyR-mediated inhibitory activity via interactions with the βGlyR subunit. Our results show that the application of IL-1β (10 ng/ml) to CeA brain slices has a biphasic effect; transiently increases and then reduces sIPSC amplitude of CeA glycinergic currents. Additionally, we performed molecular docking, site-directed mutagenesis, and whole-cell voltage-clamp electrophysiological experiments in HEK cells transfected with GlyRs containing different GlyR subunits. These data indicate that IL-1β modulates GlyR activity by establishing hydrogen bonds with at least one key amino acid residue located in the back of the loop C at the ECD domain of the βGlyR subunit. The present results suggest that IL-1β in the CeA controls glycinergic neurotransmission, possibly via interactions with the βGlyR subunit. This effect could be relevant for understanding how IL-1β released by glia modulates central processing of pain, learning and memory, and is involved in neuroinflammation.

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Serotonergic Inhibition of Action Potential Evoked Calcium Transients in NOS-Containing Mesopontine Cholinergic Neurons

Journal of Neurophysiology ◽

10.1152/jn.2000.84.3.1558 ◽

2000 ◽

Vol 84 (3) ◽

pp. 1558-1572 ◽

Cited By ~ 10

Author(s):

Christopher S. Leonard ◽

Sanjai R. Rao ◽

Takafumi Inoue

Keyword(s):

Nitric Oxide ◽

Firing Rate ◽

Rem Sleep ◽

Critical Role ◽

Brain Slices ◽

Receptor Activation ◽

Repetitive Firing ◽

Dependent Manner ◽

Laterodorsal Tegmental Nucleus ◽

State Dependent

Nitric oxide synthase (NOS)-containing mesopontine cholinergic (MPCh) neurons of the laterodorsal tegmental nucleus (LDT) are hypothesized to drive the behavioral states of waking and REM sleep through a tonic increase in firing rate which begins before and is maintained throughout these states. In principle, increased firing could elevate intracellular calcium levels and regulate numerous cellular processes including excitability, gene expression, and the activity of neuronal NOS in a state-dependent manner. We investigated whether repetitive firing, evoked by current injection and N-methyl-d-aspartate (NMDA) receptor activation, produces somatic and proximal dendritic [Ca2+]i transients and whether these transients are modulated by serotonin, a transmitter thought to play a critical role in regulating the state-dependent firing of MPCh neurons. [Ca2+]i was monitored optically from neurons filled with Ca2+ indicators in guinea pig brain slices while measuring membrane potential with sharp microelectrodes or patch pipettes. Neither hyperpolarizing current steps nor subthreshold depolarizing steps altered [Ca2+]i. In contrast, suprathreshold currents caused large and rapid increases in [Ca2+]i that were related to firing rate. TTX (1 μM) strongly attenuated this relation. Addition of tetraethylammonium (TEA, 20 mM), which resulted in Ca2+spiking on depolarization, restored the change in [Ca2+]i to pre-TTX levels. Suprathreshold doses of NMDA also produced increases in [Ca2+]i that were reduced by up to 60% by TTX. Application of 5-HT, which hyperpolarized LDT neurons without detectable changes in [Ca2+]i, suppressed both current- and NMDA-evoked increases in [Ca2+]i by reducing the number of evoked spikes and by inhibiting spike-evoked Ca2+ transients by ∼40% in the soma and proximal dendrites. This inhibition was accompanied by a subtle increase in the spike repolarization rate and a decrease in spike width, as expected for inhibition of high-threshold Ca2+ currents in these neurons. NADPH-diaphorase histochemistry confirmed that recorded cells were NOS-containing. These findings indicate the prime role of action potentials in elevating [Ca2+]i in NOS-containing MPCh neurons. Moreover, they demonstrate that serotonin can inhibit somatic and proximal dendritic [Ca2+]i increases both indirectly by reducing firing rate and directly by decreasing the spike-evoked transients. Functionally, these data suggest that spike-evoked Ca2+ signals in MPCh neurons should be largest during REM sleep when serotonin inputs are expected to be lowest even if equivalent firing rates are reached during waking. Such Ca2+ signals may function to trigger Ca2+-dependent processes including cfosexpression and nitric oxide production in a REM-specific manner.

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Contribution of Corticotropin-Releasing Factor Receptor 1 (CRF1) to Serotonin Receptor 5-HT2CR Function in Amygdala Neurons in a Neuropathic Pain Model

International Journal of Molecular Sciences ◽

10.3390/ijms20184380 ◽

2019 ◽

Vol 20 (18) ◽

pp. 4380 ◽

Cited By ~ 2

Author(s):

Guangchen Ji ◽

Volker Neugebauer

Keyword(s):

Neuropathic Pain ◽

Viral Vector ◽

Receptor Activation ◽

Pain Modulation ◽

Corticotropin Releasing Factor ◽

Central Nucleus ◽

Male Rats ◽

Facilitatory Effect ◽

Receptor Subtype ◽

Crf1 Receptor

The amygdala plays a key role in emotional-affective aspects of pain and in pain modulation. The central nucleus (CeA) serves major amygdala output functions related to emotional-affective behaviors and pain modulation. Our previous studies implicated the corticotropin-releasing factor (CRF) system in amygdala plasticity and pain behaviors in an arthritis model. We also showed that serotonin (5-HT) receptor subtype 5-HT2CR in the basolateral amygdala (BLA) contributes to increased CeA output and neuropathic pain-like behaviors. Here, we tested the novel hypothesis that 5-HT2CR in the BLA drives CRF1 receptor activation to increase CeA neuronal activity in neuropathic pain. Extracellular single-unit recordings of CeA neurons in anesthetized adult male rats detected increased activity in neuropathic rats (spinal nerve ligation model) compared to sham controls. Increased CeA activity was blocked by local knockdown or pharmacological blockade of 5-HT2CR in the BLA, using stereotaxic administration of 5-HT2CR short hairpin RNA (shRNA) viral vector or a 5-HT2CR antagonist (SB242084), respectively. Stereotaxic administration of a CRF1 receptor antagonist (NBI27914) into the BLA also decreased CeA activity in neuropathic rats and blocked the facilitatory effects of a 5-HT2CR agonist (WAY161503) administered stereotaxically into the BLA. Conversely, local (BLA) knockdown of 5-HT2CR eliminated the inhibitory effect of NBI27914 and the facilitatory effect of WAY161503 in neuropathic rats. The data suggest that 5-HT2CR activation in the BLA contributes to neuropathic pain-related amygdala (CeA) activity by engaging CRF1 receptor signaling.

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