Name: vagus nerve stimulation as a tool to induce plasticity in pathways relevant for extinction learning
Uploaded: 2015-08-21T14:00:00.000+00:00
Duration: 11 min 2 s
Description: Watch this Scientific Journal Video about Vagus Nerve Stimulation as a Tool to Induce Plasticity in Pathways Relevant for Extinction Learning at JoVE.com

This research was supported by the National Institute of Mental Health MH 086960-01A1 (Christa K. McIntyre).

The authors have no competing interests or conflicts.

Wir stellen Ihnen hier ein Protokoll, das verwendet wird, um vom Aussterben konditionierter Angst während einer einzigen Sitzung der Exposition gegenüber konditionierten Signale 19 zu erleichtern und die Plastizität in den Weg zwischen dem infralimbischen Kortex und der basolateralen Amygdala, die vermitteln können Aussterben Lernen 20 zu modulieren. Ein entscheidender Schritt für den Erfolg dieses Protokolls ist die ordnungsgemäße Lieferung der VNS bei Aussterben Ausbildung. Daher sollte be...

Klassische Angstkonditionierung stellt eine weit verbreitete Tiermodell, um die biologischen Grundlagen von Angststörungen zu untersuchen. Während der Furchtkonditionierung, ein aversiven Reiz (der unbedingten Reiz, USA, zum Beispiel ein Fuß-Schock) wird in Verbindung mit einem neutralen Reiz, wie eine Ton und / oder einem Kontext (; CS der bedingten Reiz) präsentiert. Während der Furchtkonditionierung, Verbände zwischen der CS und den USA ausgebildet. Schließlich wird die Präsentation des CS allein löst eine Angstreaktion (die konditionierte Reaktion; CR). In Furchtextinktion wird der CS wiederholt in der Abwesenheit der USA dargestellt, wodurch die CR allmählich verringern 1. So ist vom Aussterben konditionierter Angst ein aktiver Prozess, bei dem ängstlichen Verhaltensreaktionen auf neutrale Reize gedämpft werden, wenn sie nicht mehr aversive Ergebnisse vorherzusagen. Extinction konditionierter Reaktionen erfordert Konsolidierung neuer Erinnerungen, die mit gelernt Verbände konkurrieren. Ein Markenzeichen von Angststörungen ist impaired Aussterben 2-4. Somit dient Extinktion konditionierter Furcht in Tiermodellen als wichtiges Paradigma sowohl inhibitorische Lernen und als Verhaltensmodell für die menschliche Therapie von Angststörungen 5,6. Da gibt es enge Korrespondenz zwischen Angst und menschliche Angst, wird angenommen, dass diese Studien können Einblick in die biologische Natur der Angst-Erkrankungen wie posttraumatische Belastungsstörung liefern und helfen, Strategien zu entwickeln, um sie zu behandeln. Ein wichtiges Ziel der präklinischen Forschung ist zum Aussterben Lernen zu unterstützen und um zielgerichtete Plastizität in Aussterben Schaltungen zu veranlassen, vom Aussterben Lernen zu festigen. Vagusnervstimulation (VNS) ist eine minimal-invasive neuroprothetischer Ansatz, der verwendet werden könnte, um enge zeitliche und Kreislauf-spezifische Modulation von Gehirnbereichen und Synapsen in fortlaufende Aufgabe beschäftigt ist. Eine Reihe von aktuellen Studien von Michael Kilgard Gruppe an der University of Texas at Dallas habengezeigt, dass die Paarung VNS mit diskreten sensorische oder motorische Reize (zB ein Ton oder ein Hebel ziehen) ist hoch wirksam bei der Förderung der kortikale Plastizität zur Behandlung von Tinnitus 7 oder motorische Defizite zu überwinden, nach Schlaganfall 8-10. Darüber hinaus Nicht-Kontingent VNS, die innerhalb eines kurzen Zeitfenster nach dem Lernen erfolgt in ähnlicher Weise fördert die kortikale Plastizität und verbessert die Gedächtniskonsolidierung bei Ratten und beim Menschen 11-13. In Anbetracht der Rolle des Vagus in der parasympathischen Weges, ist es nicht verwunderlich, dass es bei der Modulation der Erinnerungen und der synaptischen Plastizität zu beteiligen. Hoch emotionalen Ereignisse neigen dazu, stärker Erinnerungen als Nicht-emotionalen Erinnerungen zu produzieren. Dies ist durch den Einfluss von Stresshormonen auf die Gedächtniskonsolidierung wahrscheinlich. Posttraining Verwaltung des Stresshormons Adrenalin erhöht die Speicherkonsolidierung in menschlichen und nicht-menschlichen Tieren, aber Adrenalin nicht die Blut-Hirn-Schranke 14, 15 kreuzen </sup&gt;. Daher muss spannungsinduzierte Adrenalinausschüttung das Gehirn indirekt Einfluss auf die Gedächtniskonsolidierung zu verbessern. Starke Hinweise darauf, dass der Vagus kann die Verbindung zwischen zirkulierenden Adrenalin und dem Gehirn. Miyashita und Williams 16 festgestellt, dass die systemische Verabreichung von Adrenalin erhöht Vagusnerv Brennen, und erhöhte Noradrenalin in der Amygdala 17. Die systemische Verabreichung von Adrenalin nicht verbessern Gedächtniskonsolidierung, wenn β-adrenergen Rezeptoren in der Amygdala 18 was darauf hindeutet, dass der Vagus spielt eine Rolle bei der Bahn, die emotional erregende Erfahrungen verwandelt sich in Langzeitgedächtnis blockiert. So Paarung VNS mit Ausbildung hat das Potenzial, um die Veränderungen im Gehirn, die Gedächtniskonsolidierung und der Exposition gegenAnlage Cues unterstützt in der Abwesenheit von Verstärkung erhöht die Konsolidierung des Aussterbens Lernen bei Ratten 19,20 verbessern. Hier beschreiben wir die Verwendung von VNS asa-Tool, um kortikale Plastizität fördern und Erlöschen einer konditionierten Angstreaktion zu erleichtern.

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vagus nerve stimulation as a tool to induce plasticity in pathways relevant for extinction learning

Extinction describes the process of attenuating behavioral responses to neutral stimuli when they no longer provide the reinforcement that has been maintaining the behavior. There is close correspondence between fear and human anxiety, and therefore studies of extinction learning might provide insight into the biological nature of anxiety-related disorders such as post-traumatic stress disorder, and they might help to develop strategies to treat them. Preclinical research aims to aid extinction learning and to induce targeted plasticity in extinction circuits to consolidate the newly formed memory. Vagus nerve stimulation (VNS) is a powerful approach that provides tight temporal and circuit-specific release of neurotransmitters, resulting in modulation of neuronal networks engaged in an ongoing task. VNS enhances memory consolidation in both rats and humans, and pairing VNS with exposure to conditioned cues enhances the consolidation of extinction learning in rats. Here, we provide a detailed protocol for the preparation of custom-made parts and the surgical procedures required for VNS in rats. Using this protocol we show how VNS can facilitate the extinction of conditioned fear responses in an auditory fear conditioning task. In addition, we provide evidence that VNS modulates synaptic plasticity in the pathway between the infralimbic (IL) medial prefrontal cortex and the basolateral complex of the amygdala (BLA), which is involved in the expression and modulation of extinction memory.

In diesem Abschnitt werden Beispiele für Ergebnisse, die durch die Verwendung VNS in Kombination mit vom Aussterben Lernen, um die Expression des konditionierten Angstreaktion in Ratten zu verringern gewonnen werden können. Für den Tagen 1 und 2 (Auditory Angst Anlage) wurden die Ratten auf einem Gehörfurchtkonditionierung Aufgabe, in der Fußschocks wurden mit einem Ton, gepaart geschult. Am Tag 3 (Pre-Behandlung Test), wurden Töne in der Abwesenheit von Fußschocks, um ein Einfrieren zu messen und zu schließen A...

Watch this Scientific Journal Video about Vagus Nerve Stimulation as a Tool to Induce Plasticity in Pathways Relevant for Extinction Learning at JoVE.com

Vagus Nerve Stimulation as a Tool to Induce Plasticity in Pathways Relevant for Extinction Learning

Vagusnervstimulation (VNS) hat sich als Instrument zur zielgerichteten synaptischen Plastizität im Vorderhirn zu veranlassen, eine Reihe von Verhaltensweisen ändern entstanden. Dieses Protokoll beschreibt, wie die Umsetzung VNS, um die Konsolidierung der Angst Aussterben Speicher zu erleichtern.

Vagusnervstimulation als Instrument zur Plastizität in Pathways Relevant für Extinction Learning herbei

Extinction describes the process of attenuating behavioral responses to neutral stimuli when they no longer provide the reinforcement that has been ...

vagus-nerve-stimulation-as-tool-to-induce-plasticity-pathways

Universidad San Sebastian

Research

JoVE Journal

Behavior

23.2K Aufrufe.  The University of Texas at Dallas.  Vagusnervstimulation (VNS) hat sich als Instrument zur zielgerichteten synaptischen Plastizität im Vorderhirn zu veranlassen, eine Reihe von Verhaltensweisen ändern entstanden. Dieses Protokoll beschreibt, wie die Umsetzung VNS, um die Konsolidierung der Angst Aussterben Speicher zu erleichtern. 

Serie: Vagus Nerve Stimulation as a Tool to Induce Plasticity in Pathways Relevant for Extinction Learning

Long-term Potentiation of Perforant Pathway-dentate Gyrus Synapse in Freely Behaving Mice

Studies of long-term potentiation of synaptic efficacy, an activity-dependent synaptic phenomenon having properties that make it attractive as a potential cellular mechanism underlying learning and information storage, have long been used to elucidate the physiology of various neuronal circuits in the hippocampus, amygdala, and other limbic and cortical structures. With this in mind, transgenic mouse models of neurological diseases represent useful platforms to conduct long-term&#160;potentiation (LTP) studies to develop a greater understanding of the role of genes in normal and abnormal synaptic communication in neuronal networks involved in learning, emotion and information processing. This article describes methodologies for reliably inducing LTP in the freely behaving mouse. These methodologies can be used in studies of transgenic and knockout freely&#160;behaving mouse models of neurodegenerative diseases.

Transgenic and knockout mouse models of neurological diseases are useful for studying the role of genes in normal and abnormal neurophysiology. This article describes methodologies which can be used to study long-term potentiation, a cellular mechanism which may underlie learning and memory, in transgenic and knockout freely&#160;behaving mouse models of neuropathology.

Langzeit-Potenzierung der perforant Pathway-Gyrus dentatus Synapse in Frei Behaving Mäuse

Studies of long-term potentiation of synaptic efficacy, an activity-dependent synaptic phenomenon having properties that make it attractive as a potential ...

Forschung

Verhalten

A Method for Remotely Silencing Neural Activity in Rodents During Discrete Phases of Learning

This protocol describes how to temporarily and remotely silence neuronal activity in discrete brain regions while animals are engaged in learning and memory tasks. The approach combines pharmacogenetics (Designer-Receptors-Exclusively-Activated-by-Designer-Drugs) with a behavioral paradigm (sensory preconditioning) that is designed to distinguish between different forms of learning. Specifically, viral-mediated delivery is used to express a genetically modified inhibitory G-protein coupled receptor (the Designer Receptor) into a discrete brain region in the rodent. Three weeks later, when designer receptor expression levels are high, a pharmacological agent (the Designer Drug) is administered systemically 30 min prior to a specific behavioral session. The drug has affinity for the designer receptor and thus results in inhibition of neurons that express the designer receptor, but is otherwise biologically inert. The brain region remains silenced for 2-5 hr (depending on the dose and route of administration). Upon completion of the behavioral paradigm, brain tissue is assessed for correct placement and receptor expression. This approach is particularly useful for determining the contribution of individual brain regions to specific components of behavior and can be used across any number of behavioral paradigms.

This protocol describes how to temporarily and remotely silence neuronal activity in discrete brain regions while rats are engaged in learning and memory tasks. The approach combines pharmacogenetics (Designer-Receptors-Exclusively-Activated-by-Designer-Drugs) with a behavioral paradigm (sensory preconditioning) that is designed to distinguish between different components of learning.

Ein Verfahren zum Fern Silencing neuronale Aktivität in Nagetiere Während diskreter Phasen des Lernens

This protocol describes how to temporarily and remotely silence neuronal activity in discrete brain regions while animals are engaged in learning and ...

Extinction Training During the Reconsolidation Window Prevents Recovery of Fear

Fear is maladaptive when it persists long after circumstances have become safe. It is therefore crucial to develop an approach that persistently prevents the return of fear. Pavlovian fear-conditioning paradigms are commonly employed to create a controlled, novel fear association in the laboratory. After pairing an innocuous stimulus (conditioned stimulus, CS) with an aversive outcome (unconditioned stimulus, US) we can elicit a fear response (conditioned response, or CR) by presenting just the stimulus alone1,2 . Once fear is acquired, it can be diminished using extinction training, whereby the conditioned stimulus is repeatedly presented without the aversive outcome until fear is no longer expressed3. This inhibitory learning creates a new, safe representation for the CS, which competes for expression with the original fear memory4. Although extinction is effective at inhibiting fear, it is not permanent. Fear can spontaneously recover with the passage of time. Exposure to stress or returning to the context of initial learning can also cause fear to resurface3,4.
Our protocol addresses the transient nature of extinction by targeting the reconsolidation window to modify emotional memory in a more permanent manner. Ample evidence suggests that reactivating a consolidated memory returns it to a labile state, during which the memory is again susceptible to interference5-9. This window of opportunity appears to open shortly after reactivation and close approximately 6hrs later5,11,16, although this may vary depending on the strength and age of the memory15. By allowing new information to incorporate into the original memory trace, this memory may be updated as it reconsolidates10,11. Studies involving non-human animals have successfully blocked the expression of fear memory by introducing pharmacological manipulations within the reconsolidation window, however, most agents used are either toxic to humans or show equivocal effects when used in human studies12-14. Our protocol addresses these challenges by offering an effective, yet non-invasive, behavioral manipulation that is safe for humans.
By prompting fear memory retrieval prior to extinction, we essentially trigger the reconsolidation process, allowing new safety information (i.e., extinction) to be incorporated while the fear memory is still susceptible to interference. A recent study employing this behavioral manipulation in rats has successfully blocked fear memory using these temporal parameters11. Additional studies in humans have demonstrated that introducing new information after the retrieval of previously consolidated motor16, episodic17, or declarative18 memories leads to interference with the original memory trace14. We outline below a novel protocol used to block fear recovery in humans.

Conditioned fear can be diminished through an inhibitory process called extinction, but can resurface under conditions such as the passage of time or exposure to stress. Our protocol presents a novel way of preventing fear recovery by introducing extinction during the reconsolidation window (the re-storage phase of a reactivated memory).

Extinction Training Während der Rückverfestigung Fenster Verhindert Recovery-of Fear

Fear is maladaptive when it persists long after circumstances have become safe. It is therefore crucial to develop an approach that persistently prevents ...

Neurowissenschaften

Ex Vivo Optogenetic Dissection of Fear Circuits in Brain Slices

Optogenetic approaches are now widely used to study the function of neural populations and circuits by combining targeted expression of light-activated proteins and subsequent manipulation of neural activity by light. Channelrhodopsins (ChRs) are light-gated cation-channels and when fused to a fluorescent protein their expression allows for visualization and concurrent activation of specific cell types and their axonal projections in defined areas of the brain. Via stereotactic injection of viral vectors, ChR fusion proteins can be constitutively or conditionally expressed in specific cells of a defined brain region, and their axonal projections can subsequently be studied anatomically and functionally via ex vivo optogenetic activation in brain slices. This is of particular importance when aiming to understand synaptic properties of connections that could not be addressed with conventional electrical stimulation approaches, or in identifying novel afferent and efferent connectivity that was previously poorly understood. Here, a few examples illustrate how this technique can be applied to investigate these questions to elucidating fear-related circuits in the amygdala. The amygdala is a key region for acquisition and expression of fear, and storage of fear and emotional memories. Many lines of evidence suggest that the medial prefrontal cortex (mPFC) participates in different aspects of fear acquisition and extinction, but its precise connectivity with the amygdala is just starting to be understood. First, it is shown how ex vivo optogenetic activation can be used to study aspects of synaptic communication between mPFC afferents and target cells in the basolateral amygdala (BLA). Furthermore, it is illustrated how this ex vivo optogenetic approach can be applied to assess novel connectivity patterns using a group of GABAergic neurons in the amygdala, the paracapsular intercalated cell cluster (mpITC), as an example.

Ex Vivo Optogenetic Dissection of Fear Circuits in Brain Slices

Optogenetic approaches are widely used to manipulate neural activity and assess the consequences for brain function. Here, a technique is outlined that&#160;upon in vivo expression of the optical activator Channelrhodopsin, allows for ex vivo analysis of synaptic properties of specific long range and local neural connections in fear-related circuits.

Ex Vivo optogenetische Dissection of Fear Schaltkreise in Hirnschnitten

Optogenetic approaches are now widely used to study the function of neural populations and circuits by combining targeted expression of light-activated ...

Assessment of Long-term Depression Induction in Adult Cerebellar Slices

Synaptic plasticity provides a mechanism for learning and memory. For cerebellar motor learning, long-term depression (LTD) of synaptic transmissions from parallel fibers (PF) to Purkinje cells (PC) is considered the basis for motor learning, and deficiencies of both LTD and motor learning are observed in various gene-manipulated animals. Common motor learning sets, such as adaptation of the optokinetic reflex (OKR), the vestibular-ocular reflex (VOR), and rotarod test were used for evaluation of motor learning ability. However, results obtained from the GluA2-carboxy terminus modified knock-in mice demonstrated normal adaptation of the VOR and the OKR, despite lacking PF-LTD. In that report, induction of LTD was only attempted using one type of stimulation protocol at room temperature. Thus, conditions to induce cerebellar LTD were explored in the same knock-in mutants using various protocols at near physiological temperature. Finally, we found stimulation protocols, by which LTD could be induced in these gene-manipulated mice. In this study, a set of protocols are proposed to evaluate LTD-induction, which will more accurately allow examination of the causal relationship between LTD and motor learning. In conclusion, experimental conditions are crucial when evaluating LTD in gene-manipulated mice.

In some gene-manipulated animals, using a single protocol may fail to induce LTD in cerebellar Purkinje cells, and there may be a discrepancy between LTD and motor learning. Multiple protocols are necessary to assess LTD-induction in gene-manipulated animals. Standard protocols are shown.

Bewertung der Langzeit-Depressionsinduktion bei erwachsenen Cerebellarscheiben

Synaptic plasticity provides a mechanism for learning and memory. For cerebellar motor learning, long-term depression (LTD) of synaptic transmissions from ...

Vagus Nerve Stimulation As an Adjunctive Neurostimulation Tool in Treatment-resistant Depression

Vagus nerve stimulation (VNS) is an approved neurostimulation therapy. The purpose of the method is to treat patients with therapy-resistant depression (TRD). VNS exhibits antidepressive and stabilizing effects. This method is particularly useful as a long-term treatment, in which up to two-thirds of patients respond. The vagus nerve stimulator is positioned on the left vagus nerve during a surgical procedure and is activated telemetrically by a wand connected to a handheld computerized device. The treating physician can perform various adjustments of the vagus nerve stimulator during in-office visits (e.g., by modifying stimulation intensity or stimulation frequency) to achieve maximum therapeutic effects with low side effects. Set-up of the device usually takes several months. Typical side effects include wound infection, temporary salivation, coughing, paralysis of the vocal cords, bradycardia, or even asystole. The patient can stop the VNS by placing a magnet over the generator. The current protocol describes delivery of the specific stimulation tool and methods for adjusting the tuning parameters to achieve the best remission rates in patients with TRD.

Vagus nerve stimulation (VNS) has been shown to be effective as an adjunct treatment for treatment-resistant depression (TRD). VNS leads to antidepressive and antisuicidal effects and quality of life improvements. This protocol offers a step-by-step guide to managing and adjusting a vagus nerve stimulator for efficient treatment of TRD.

Vagusnerv-Stimulation als Zusatztherapie Neurostimulation Instrument bei behandlungsresistenter Depression

Vagus nerve stimulation (VNS) is an approved neurostimulation therapy. The purpose of the method is to treat patients with therapy-resistant depression ...

Medizin

Preparation of Peripheral Nerve Stimulation Electrodes for Chronic Implantation in Rats

Peripheral nerve cuff electrodes have long been used in the neurosciences and related fields for stimulation of, for example, vagus or sciatic nerves. Several recent studies have demonstrated the effectiveness of chronic VNS in enhancing central nervous system plasticity to improve motor rehabilitation, extinction learning, and sensory discrimination. Construction of chronically implantable devices for use in such studies is challenging due to rats&#8217; small size, and typical protocols require extensive training of personnel and time-consuming microfabrication methods. Alternatively, commercially available implantable cuff electrodes can be purchased at a significantly higher cost. In this protocol, we present a simple, low-cost method for construction of small, chronically implantable peripheral nerve cuff electrodes for use in rats. We validate the short and long-term reliability of our cuff electrodes by demonstrating that VNS in ketamine/xylazine anesthetized rats produces decreases in breathing rate consistent with activation of the Hering-Breuer reflex, both at the time of implantation and up to 10 weeks after device implantation. We further demonstrate the suitability of the cuff electrodes for use in chronic stimulation studies by pairing VNS with skilled lever press performance to induce motor cortical map plasticity.

Existing approaches for constructing chronically implantable peripheral nerve cuff electrodes for use in small rodents often require specialized equipment and/or highly trained personnel. In this protocol we demonstrate a simple, low-cost approach for fabricating chronically implantable cuff electrodes, and demonstrate their effectiveness for vagus nerve stimulation (VNS) in rats.

Vorbereitung von peripheren Nervenstimulationselektroden für die chronische Implantation bei Ratten

Peripheral nerve cuff electrodes have long been used in the neurosciences and related fields for stimulation of, for example, vagus or sciatic nerves. ...

Ex Vivo Optogenetic Interrogation of Long-Range Synaptic Transmission and Plasticity from Medial Prefrontal Cortex to Lateral Entorhinal Cortex

Studying the physiological properties of specific synapses in the brain, and how they undergo plastic changes, is a key challenge in modern neuroscience. Traditional in vitro electrophysiological techniques use electrical stimulation to evoke synaptic transmission. A major drawback of this method is its nonspecific nature; all axons in the region of the stimulating electrode will be activated, making it difficult to attribute an effect to a particular afferent connection. This issue can be overcome by replacing electrical stimulation with optogenetic-based stimulation. We describe a method for combining optogenetics with in vitro patch-clamp recordings. This is a powerful tool for the study of both basal synaptic transmission and synaptic plasticity of precise anatomically defined synaptic connections and is applicable to almost any pathway in the brain. Here, we describe the preparation and handling of a viral vector encoding channelrhodopsin protein for surgical injection into a pre-synaptic region of interest (medial prefrontal cortex) in the rodent brain and making of acute slices of downstream target regions (lateral entorhinal cortex). A detailed procedure for combining patch-clamp recordings with synaptic activation by light stimulation to study short- and long-term synaptic plasticity is also presented. We discuss examples of experiments that achieve pathway- and cell-specificity by combining optogenetics and Cre-dependent cell labeling. Finally, histological confirmation of the pre-synaptic region of interest is described along with biocytin labeling of the post-synaptic cell, to allow further identification of the precise location and cell type.

Ex Vivo Optogenetic Interrogation of Long-Range Synaptic Transmission and Plasticity from Medial Prefrontal Cortex to Lateral Entorhinal Cortex

Here we present a protocol describing viral transduction of discrete brain regions with optogenetic constructs to permit synapse-specific electrophysiological characterization in acute rodent brain slices.

Ex vivo Optogenetische Befragung der synaptischen Übertragung und Plastizität über große Entfernungen vom medialen präfrontalen Kortex zum lateralen entohinalen Kortex

Studying the physiological properties of specific synapses in the brain, and how they undergo plastic changes, is a key challenge in modern neuroscience. ...

Using Optogenetics to Reverse Neuroplasticity and Inhibit Cocaine Seeking in Rats

This protocol demonstrates the steps needed to use optogenetic tools to reverse cocaine-induced plasticity at thalamo-amygdala circuits to reduce subsequent cocaine seeking behaviors in the rat. In our research, we had found that when rats self-administer intravenous cocaine paired with an audiovisual cue, synapses formed at inputs from the medial geniculate nucleus of the thalamus (MGN) onto principal neurons of the lateral amygdala (LA) become stronger as the cue-cocaine association is learned. We hypothesized that reversal of the cocaine-induced plasticity at these synapses would reduce cue-motivated cocaine seeking behavior. In order to accomplish this type of neuromodulation in vivo, we wanted to induce synaptic long-term depression (LTD), which decreases the strength of MGN-LA synapses. To this end, we used optogenetics, which allows neuromodulation of brain circuits using light. The excitatory opsin oChiEF was expressed on presynaptic MGN terminals in the LA by infusing an AAV containing oChiEF into the MGN. Optical fibers were then implanted in the LA and 473 nm laser light was pulsed at a frequency of 1 Hz for 15 minutes to induce LTD and reverse cocaine induced plasticity. This manipulation produces a long-lasting reduction in the ability of cues associated with cocaine to induce drug seeking actions.

The methods described here outline a procedure used to optogenetically reverse cocaine-induced plasticity in a behaviorally-relevant circuit in rats. Sustained low-frequency optical stimulation of thalamo-amygdala synapses induces long-term depression (LTD). In vivo optogenetically-induced LTD in cocaine-experienced rats resulted in the subsequent attenuation of cue-motivated drug seeking.

Verwendung von Optogenetik zur Umkehrung der Neuroplastizität und zur Hemmung der Kokainsuche bei Ratten

This protocol demonstrates the steps needed to use optogenetic tools to reverse cocaine-induced plasticity at thalamo-amygdala circuits to reduce ...

Abdominale VNS zur Behandlung von Entzündungszuständen in Rattenmodellen

Implantation Surgery for Abdominal Vagus Nerve Stimulation and Recording Studies in Awake Rats

Abdominal vagus nerve stimulation (VNS) can be applied to the subdiaphragmatic branch of the vagus nerve of rats. Due to its anatomical location, it does not have any respiratory and cardiac off-target effects commonly associated with cervical VNS. The lack of respiratory and cardiac off-target effects means that the intensity of stimulation does not need to be lowered to reduce side effects commonly experienced during cervical VNS. Few recent studies demonstrate the anti-inflammatory effects of abdominal VNS in rat models of inflammatory bowel disease, rheumatoid arthritis, and glycemia reduction in a rat model of type 2 diabetes. Rat is a great model to explore the potential of this technology because of the well-established anatomy of the vagus nerve, the large size of the nerve that allows easy handling, and the availability of many disease models. Here, we describe the methods for cleaning and sterilizing the abdominal VNS electrode array and surgical protocol in rats. We also describe the technology required for confirmation of suprathreshold stimulation by recording evoked compound action potentials. Abdominal VNS has the potential to offer selective, effective treatment for a variety of conditions, including inflammatory diseases, and the application is expected to expand similarly to cervical VNS.

Autor im Rampenlicht: Erforschung von abdominalen VNS bei entzündlichen Erkrankungen

The present protocol describes the surgical technique for implanting an electrode array onto the abdominal vagus nerve in rats, along with methods for chronic electrophysiology testing and stimulation using the implanted device.

Implantationschirurgie zur Stimulation des abdominalen Vagusnervs und Aufzeichnungsstudien an wachen Ratten

Abdominal vagus nerve stimulation (VNS) can be applied to the subdiaphragmatic branch of the vagus nerve of rats. Due to its anatomical location, it does ...