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Mayberry HK, Rinker JA, Chandler LJ. Effect of chronic alcohol exposure and single-prolonged stress on conditioned fear behavior. Behav Brain Res 2024; 477:115294. [PMID: 39419182 DOI: 10.1016/j.bbr.2024.115294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2024] [Revised: 08/17/2024] [Accepted: 10/14/2024] [Indexed: 10/19/2024]
Abstract
The present study investigated the impact of chronic intermittent ethanol (CIE) exposure and single-prolonged stress (SPS) on the acquisition of fear memories in both male and female Wistar rats. Adult rats were first subjected to CIE by vapor inhalation followed by SPS. Following a subsequent 8-day incubation period, the rats underwent a Pavlovian fear conditioning procedure (tone-shock pairings) followed by cued-tone extinction training, and then testing of extinction recall memory and fear renewal memory. In control animals that had not been exposed to either CIE or SPS, female rats exhibited significantly lower levels of freezing compared to male rats during tone-shock pairings. This lower level of freezing in female rats during conditioning was associated with an increased speed of movement compared to males. Also compared to males, female rats exhibited lower levels of fear extinction, recall, and renewal. Exposure to CIE, SPS, or CIE+SPS had no effect on freezing during the cued-conditioning, extinction, or extinction recall phases of the testing procedure in either sex. In fear renewal, CIE exposure decreased freezing in male but not female rats, while SPS increased freezing in female but not male rats. CIE exposure significantly reduced freezing during the fear renewal phase. Taken together, these results provide further evidence that male and female rats adopt different avoidance strategies for threat responding. These results also revealed that prior exposure to CIE, SPS, or CIE+SPS had minimal effects on threat responding using conditioned freezing as an indicator of fear responsivity.
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Affiliation(s)
- Heyam K Mayberry
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA
| | - Jennifer A Rinker
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA
| | - L Judson Chandler
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, USA.
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2
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Loetscher KB, Goldfarb EV. Integrating and fragmenting memories under stress and alcohol. Neurobiol Stress 2024; 30:100615. [PMID: 38375503 PMCID: PMC10874731 DOI: 10.1016/j.ynstr.2024.100615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 02/03/2024] [Accepted: 02/06/2024] [Indexed: 02/21/2024] Open
Abstract
Stress can powerfully influence the way we form memories, particularly the extent to which they are integrated or situated within an underlying spatiotemporal and broader knowledge architecture. These different representations in turn have significant consequences for the way we use these memories to guide later behavior. Puzzlingly, although stress has historically been argued to promote fragmentation, leading to disjoint memory representations, more recent work suggests that stress can also facilitate memory binding and integration. Understanding the circumstances under which stress fosters integration will be key to resolving this discrepancy and unpacking the mechanisms by which stress can shape later behavior. Here, we examine memory integration at multiple levels: linking together the content of an individual experience, threading associations between related but distinct events, and binding an experience into a pre-existing schema or sense of causal structure. We discuss neural and cognitive mechanisms underlying each form of integration as well as findings regarding how stress, aversive learning, and negative affect can modulate each. In this analysis, we uncover that stress can indeed promote each level of integration. We also show how memory integration may apply to understanding effects of alcohol, highlighting extant clinical and preclinical findings and opportunities for further investigation. Finally, we consider the implications of integration and fragmentation for later memory-guided behavior, and the importance of understanding which type of memory representation is potentiated in order to design appropriate interventions.
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Affiliation(s)
| | - Elizabeth V. Goldfarb
- Department of Psychiatry, Yale University, USA
- Department of Psychology, Yale University, USA
- Wu Tsai Institute, Yale University, USA
- National Center for PTSD, West Haven VA, USA
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3
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Zhang L, Wang Y, Li S, Otani S, Chen F. Post-stress Social Interaction and 3-Cyano-N-(1,3-Diphenyl-1H-Pyrazol-5-yl) Benzamide Treatment Attenuate Depressive-like Behavior Induced by Repeated Social Defeat Stress. Neuroscience 2024; 538:11-21. [PMID: 38103860 DOI: 10.1016/j.neuroscience.2023.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 11/23/2023] [Accepted: 12/11/2023] [Indexed: 12/19/2023]
Abstract
Persistent stress increases the probability for developing depression significantly thereafter. Repeated social defeat stress is a widely used model to investigate depressive-like behavior in preclinical models. Hence, the repeated social defeat stress model provided an ideal animal model, through which the hypotheses of prevention and treatment can be investigated. We have successfully induced depressive-like behavior for male C57BL/6J mice with this model. Here, we reported that certain level of during-stress social interactions with single female or multiple male peer(s) exerted a positive role in preventing the development of depressive-like behavior induced by repeated social defeat stress. Our data suggested that the stress-susceptible mice may benefit from positive social interaction, which reduces the chance for depressive-like behavior development. Since numerous studies indicate that the metabotropic glutamate receptor 5 (mGluR5) plays an important role in various cognitive functions, we further investigate the treatment effect of 3-cyano-N-(1,3-diphenyl-1H-pyrazol-5-yl) benzamide (CDPPB) on the depressive-like behavior induced by repeated social defeat stress. Most importantly, robust anti-depressant effects have been achieved through modulating the mGluR5 function. We found that single oral dose administration of CDPPB (20 mg/kg), to some extent, alleviated the social avoidance behaviors for the stress-susceptible mice. Our data implies that the CDPPB, a positive allosteric modulator of mGluR5, is a promising anti-depressant candidate with limited side effect.
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Affiliation(s)
- Liangui Zhang
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai 200030, China.
| | - Ying Wang
- Core Research Facilities, Southern University of Science and Technology, Shenzhen 518055, China.
| | - Shengtian Li
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai 200030, China.
| | - Satoru Otani
- Vision Institute, CNRS - INSERM - Sorbonne University, Paris 75012, France.
| | - Fujun Chen
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai 200030, China.
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Lonnberg A, Logrip ML, Kuznetsov A. Mechanisms of alcohol influence on fear conditioning: a computational model. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.12.30.573310. [PMID: 38260700 PMCID: PMC10802259 DOI: 10.1101/2023.12.30.573310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
A connection between stress-related illnesses and alcohol use disorders is extensively documented. Fear conditioning is a standard procedure used to study stress learning and links it to the activation of amygdala circuitry. However, the connection between the changes in amygdala circuit and function induced by alcohol and fear conditioning is not well established. We introduce a computational model to test the mechanistic relationship between amygdala functional and circuit adaptations during fear conditioning and the impact of acute vs. repeated alcohol exposure. In accordance with experiments, both acute and prior repeated alcohol decreases speed and robustness of fear extinction in our simulations. The model predicts that, first, the delay in fear extinction in alcohol is mostly induced by greater activation of the basolateral amygdala (BLA) after fear acquisition due to alcohol-induced modulation of synaptic weights. Second, both acute and prior repeated alcohol shifts the amygdala network away from the robust extinction regime by inhibiting the activity in the central amygdala (CeA). Third, our model predicts that fear memories formed in acute or after chronic alcohol are more connected to the context. Thus, the model suggests how circuit changes induced by alcohol may affect fear behaviors and provides a framework for investigating the involvement of multiple neuromodulators in this neuroadaptive process.
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Affiliation(s)
- Adam Lonnberg
- University of Evansville, Department of Mathematics, Indianapolis, Indiana, USA
| | - Marian L. Logrip
- Indiana University-Purdue University, Department of Psychology, Indianapolis, Indiana, USA
| | - Alexey Kuznetsov
- Indiana University-Purdue University, Department of Mathematical Sciences, Indianapolis, Indiana, USA
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Persistent disruption of overexpectation learning after inactivation of the lateral orbitofrontal cortex in male rats. Psychopharmacology (Berl) 2023; 240:501-511. [PMID: 35932299 DOI: 10.1007/s00213-022-06198-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 07/20/2022] [Indexed: 10/16/2022]
Abstract
RATIONALE AND OBJECTIVE Learning to inhibit acquired fear responses is fundamental to adaptive behavior. Two procedures that support such learning are extinction and overexpectation. In extinction, an expected outcome is omitted, whereas in overexpectation two individually trained cues are presented in compound to induce an expectation of a greater outcome than that delivered. Previously, we showed that inactivation of the lateral orbitofrontal cortex (lOFC) in experimentally naïve male rats causes a mild impairment in extinction learning but a profound one in overexpectation. The mild extinction impairment was also transient; that is, it was absent in a cohort of rats that had prior history of inhibitory training (overexpectation, extinction) and their associated controls. This raised the question whether lOFC involvement in overexpectation could likewise be attenuated by prior experience. METHODS Using a muscimol/baclofen cocktail, we inactivated the lOFC during overexpectation training in rats with prior associative learning history (extinction, overexpectation, control) and examined its contribution to reducing learned fear. RESULTS Inactivating the lOFC during compound training in overexpectation persistently disrupted fear reduction on test in naïve rats and regardless of prior experience. Additionally, we confirm that silencing the lOFC only resulted in a mild impairment in extinction learning in naïve rats. CONCLUSION We show that prior associative learning experience did not mitigate the deficit in overexpectation caused by lOFC inactivation. Our findings emphasize the importance of this region for this particular form of fear reduction and broaden our understanding of the conditions in which the lOFC modulates behavioral inhibition.
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Zhan B, Zhu Y, Xia J, Li W, Tang Y, Beesetty A, Ye JH, Fu R. Comorbidity of Post-Traumatic Stress Disorder and Alcohol Use Disorder: Animal Models and Associated Neurocircuitry. Int J Mol Sci 2022; 24:ijms24010388. [PMID: 36613829 PMCID: PMC9820348 DOI: 10.3390/ijms24010388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Revised: 12/12/2022] [Accepted: 12/22/2022] [Indexed: 12/28/2022] Open
Abstract
Post-traumatic stress disorder (PTSD) and alcohol use disorder (AUD) are prevalent neuropsychiatric disorders and frequently co-occur concomitantly. Individuals suffering from this dual diagnosis often exhibit increased symptom severity and poorer treatment outcomes than those with only one of these diseases. Lacking standard preclinical models limited the exploration of neurobiological mechanisms underlying PTSD and AUD comorbidity. In this review, we summarize well-accepted preclinical model paradigms and criteria for developing successful models of comorbidity. We also outline how PTSD and AUD affect each other bidirectionally in the nervous nuclei have been heatedly discussed recently. We hope to provide potential recommendations for future research.
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Affiliation(s)
- Bo Zhan
- Department of Anatomy, School of Medicine, Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen 518107, China
| | - Yingxin Zhu
- Department of Anatomy, School of Medicine, Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen 518107, China
| | - Jianxun Xia
- Department of Basic Medical Sciences, Yunkang School of Medicine and Health, Nanfang College, Guangzhou 510970, China
| | - Wenfu Li
- Department of Anatomy, School of Medicine, Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen 518107, China
| | - Ying Tang
- Department of Biology, School of Life Science, Southern University of Science and Technology, Shenzhen 518055, China
| | - Anju Beesetty
- Department of Anesthesiology, Pharmacology, Physiology & Neuroscience, Rutgers, New Jersey Medical School, The State University of New Jersey, Newark, NJ 07103, USA
| | - Jiang-Hong Ye
- Department of Anesthesiology, Pharmacology, Physiology & Neuroscience, Rutgers, New Jersey Medical School, The State University of New Jersey, Newark, NJ 07103, USA
- Correspondence: (J.-H.Y.); (R.F.)
| | - Rao Fu
- Department of Anatomy, School of Medicine, Shenzhen Campus of Sun Yat-sen University, Sun Yat-sen University, Shenzhen 518107, China
- Correspondence: (J.-H.Y.); (R.F.)
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Lawson K, Scarlata MJ, Cho WC, Mangan C, Petersen D, Thompson HM, Ehnstrom S, Mousley AL, Bezek JL, Bergstrom HC. Adolescence alcohol exposure impairs fear extinction and alters medial prefrontal cortex plasticity. Neuropharmacology 2022; 211:109048. [PMID: 35364101 PMCID: PMC9067297 DOI: 10.1016/j.neuropharm.2022.109048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 02/26/2022] [Accepted: 03/26/2022] [Indexed: 10/18/2022]
Abstract
After experiencing a traumatic event people often turn to alcohol to cope with symptoms. In those with post-traumatic stress disorder (PTSD) and a co-occurring alcohol use disorder (AUD), PTSD symptoms can worsen, suggesting that alcohol changes how traumatic memory is expressed. The objective of this series of experiments is to identify how alcohol drinking (EtOH), following cued fear conditioning and extinction, impacts fear expression in mice. Molecular (activity-regulated cytoskeleton-associated protein, Arc/arg3.1) and structural (dendrite and spine morphometry) markers of neuronal plasticity were measured following remote extinction retrieval. Mouse age (adolescent and adult) and sex were included as interacting variables in a full factorial design. Females drank more EtOH than males and adolescents drank more EtOH than adults. Adolescent females escalated EtOH intake across drinking days. Adolescent drinkers exhibited more conditioned freezing during extinction retrieval, an effect that persisted for at least 20 days. Heightened cued freezing in the adolescent group was associated with greater Arc/arg3.1 expression in layer (L) 2/3 prelimbic (PL) cortex, greater spine density, and reduced basal dendrite complexity. In adults, drinking was associated with reduced L2/3 infralimbic (IL) Arc expression but no behavioral differences. Few sex interactions were uncovered throughout. Overall, these data identify prolonged age-related differences in alcohol-induced fear extinction impairment and medial prefrontal cortex neuroadaptations.
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Affiliation(s)
- K Lawson
- Department of Psychological Science, Program in Neuroscience and Behavior, Vassar College, Poughkeepsie, NY, USA
| | - M J Scarlata
- Department of Psychological Science, Program in Neuroscience and Behavior, Vassar College, Poughkeepsie, NY, USA
| | - W C Cho
- Department of Psychological Science, Program in Neuroscience and Behavior, Vassar College, Poughkeepsie, NY, USA
| | - C Mangan
- Department of Psychological Science, Program in Neuroscience and Behavior, Vassar College, Poughkeepsie, NY, USA
| | - D Petersen
- Department of Psychological Science, Program in Neuroscience and Behavior, Vassar College, Poughkeepsie, NY, USA
| | - H M Thompson
- Department of Psychological Science, Program in Neuroscience and Behavior, Vassar College, Poughkeepsie, NY, USA
| | - S Ehnstrom
- Department of Psychological Science, Program in Neuroscience and Behavior, Vassar College, Poughkeepsie, NY, USA
| | - A L Mousley
- Department of Psychological Science, Program in Neuroscience and Behavior, Vassar College, Poughkeepsie, NY, USA
| | - J L Bezek
- Department of Psychological Science, Program in Neuroscience and Behavior, Vassar College, Poughkeepsie, NY, USA
| | - H C Bergstrom
- Department of Psychological Science, Program in Neuroscience and Behavior, Vassar College, Poughkeepsie, NY, USA.
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Chandler LJ, Vaughan DT, Gass JT. Adolescent Alcohol Exposure Results in Sex-specific Alterations in Conditioned Fear Learning and Memory in Adulthood. Front Pharmacol 2022; 13:837657. [PMID: 35211024 PMCID: PMC8861326 DOI: 10.3389/fphar.2022.837657] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 01/19/2022] [Indexed: 11/26/2022] Open
Abstract
The present study used auditory fear conditioning to assess the impact of repeated binge-like episodes of alcohol exposure during adolescence on conditioned fear in adulthood. Male and female Long-Evans rats were subjected to adolescent intermittent ethanol (AIE) exposure by vapor inhalation between post-natal day 28 and 44. After aging into adulthood, rats then underwent fear conditioning by exposure to a series of tone-shock pairings. This was followed by cued-tone extinction training, and then testing of fear recovery. In male rats, AIE exposure enhanced conditioned freezing but did not alter the time-course of extinction of cued-tone freezing. During subsequent assessment of fear recovery, AIE exposed rats exhibited less freezing during contextual fear renewal, but greater freezing during extinction recall and spontaneous recovery. Compared to males, female rats exhibited significantly lower levels of freezing during fear conditioning, more rapid extinction of freezing behavior, and significantly lower levels of freezing during the tests of fear recovery. Unlike males that were all classified as high conditioners; female rats could be parsed into either a high or low conditioning group. However, irrespective of their level of conditioned freezing, both the high and low conditioning groups of female rats exhibited rapid extinction of conditioned freezing behavior and comparatively low levels of freezing in tests of fear recovery. Regardless of group classification, AIE had no effect on freezing behavior in female rats during acquisition, extinction, or fear recovery. Lastly, exposure of male rats to the mGlu5 positive allosteric modulator CDPPB prevented AIE-induced alterations in freezing. Taken together, these observations demonstrate sex-specific changes in conditioned fear behaviors that are reversible by pharmacological interventions that target mGlu5 receptor activation.
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Affiliation(s)
- L Judson Chandler
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, United States
| | - Dylan T Vaughan
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC, United States
| | - Justin T Gass
- Department of Biomedical Sciences, East Tennessee State University, Johnson City, TN, United States
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Brown RW, Varnum CG, Wills LJ, Peeters LD, Gass JT. Modulation of mGlu5 improves sensorimotor gating deficits in rats neonatally treated with quinpirole through changes in dopamine D2 signaling. Pharmacol Biochem Behav 2021; 211:173292. [PMID: 34710401 PMCID: PMC9176413 DOI: 10.1016/j.pbb.2021.173292] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/19/2021] [Accepted: 10/20/2021] [Indexed: 12/19/2022]
Abstract
This study analyzed whether the positive allosteric modulator of metabotropic glutamate receptor type 5 (mGlu5) 3-Cyano-N-(1,3-diphenyl-1H-pyrazol-5-yl) benzamide (CDPPB) would alleviate deficits in prepulse inhibition (PPI) and affect dopamine (DA) D2 signaling in the dorsal striatum and prefrontal cortex (PFC) in the neonatal quinpirole (NQ) model of schizophrenia (SZ). Male and female Sprague-Dawley rats were neonatally treated with either saline (NS) or quinpirole HCL (1 mg/kg; NQ), a DAD2 receptor agonist, from postnatal days (P) 1-21. Rats were raised to P44 and behaviorally tested on PPI from P44-P48. Before each trial, rats were subcutaneous (sc) administered saline or CDPPB (10 mg/kg or 30 mg/kg). On P50, rats were given a spontaneous locomotor activity test after CDPPB or saline administration. On P51, the dorsal striatum and PFC were evaluated for both arrestin-2 (βA-2) and phospho-AKT protein levels. NQ-treated rats demonstrated a significant deficit in PPI, which was alleviated to control levels by the 30 mg/kg dose of CDPPB. There were no significant effects of CDPPB on locomotor activity. NQ treatment increased βA-2 and decreased phospho-AKT in both the dorsal striatum and PFC, consistent with an increase DAD2 signaling. The 30 mg/kg dose of CDPPB significantly reversed changes in βA-2 in the dorsal striatum and PFC and phospho-AKT in the PFC equivalent to controls. Both doses of CDPPB produced a decrease of phospho-AKT in the PFC compared to controls. This study revealed that a mGlu5 positive allosteric modulator was effective to alleviate PPI deficits and striatal DAD2 signaling in the NQ model of SZ.
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Affiliation(s)
- Russell W Brown
- Department of Biomedical Sciences James H. Quillen College of Medicine, East Tennessee State University Johnson City, TN 37614, United States of America.
| | - Christopher G Varnum
- Department of Biomedical Sciences James H. Quillen College of Medicine, East Tennessee State University Johnson City, TN 37614, United States of America
| | - Liza J Wills
- Department of Biomedical Sciences James H. Quillen College of Medicine, East Tennessee State University Johnson City, TN 37614, United States of America
| | - Loren D Peeters
- Department of Biomedical Sciences James H. Quillen College of Medicine, East Tennessee State University Johnson City, TN 37614, United States of America
| | - Justin T Gass
- Department of Biomedical Sciences James H. Quillen College of Medicine, East Tennessee State University Johnson City, TN 37614, United States of America
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10
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Smiley CE, McGonigal JT, Nimchuk KE, Gass JT. Optogenetic manipulation of the prelimbic cortex during fear memory reconsolidation alters fear extinction in a preclinical model of comorbid PTSD/AUD. Psychopharmacology (Berl) 2021; 238:3193-3206. [PMID: 34347171 DOI: 10.1007/s00213-021-05935-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Accepted: 07/12/2021] [Indexed: 12/27/2022]
Abstract
RATIONALE AND OBJECTIVE Post-traumatic stress disorder (PTSD) and alcohol use disorder (AUD) are disorders of learning and memory that often occur comorbidly. Exposure to trauma-related cues can increase alcohol intake in PTSD patients that are using alcohol to self-medicate. The recurrence of anxiety symptoms with subsequent alcohol use may initiate a destructive cycle where stress and alcohol exposure impair the function of the prefrontal cortex (PFC). While the incidence of these disorders has steadily increased, current therapies and treatments often lack efficacy. Thus, investigation into the underlying neurocircuitry responsible for the establishment and maintenance of these disorders is necessary to develop novel treatment targets. METHODS The present study examined the effects of ethanol exposure on the ability to create new learned associations around previously conditioned fear cues in a rat model. Animals were exposed to fear conditioning followed by chronic intermittent ethanol to translationally model trauma exposure followed by alcohol abuse. Optogenetics was used to inhibit the prelimbic (PrL) or infralimbic (IfL) cortex during fear memory reconsolidation, and fear behaviors were measured during subsequent extinction and spontaneous recovery tests. Results and conclusion Chronic ethanol exposure led to deficits in fear extinction learning and increased freezing during spontaneous recovery, both of which were prevented following inhibition of the PrL, but not the IfL, during memory reconsolidation. These results support the involvement of the PrL in fear learning and memory, and strongly suggest that the PrL could serve as a potential target for the treatment of the learning and memory deficits that occur following exposure to stress and alcohol.
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Affiliation(s)
- C E Smiley
- Department of Neuroscience, Basic Science Building, Medical University of South Carolina, 173 Ashley Avenue, Room 403, Charleston, SC, 29425, USA.
| | - J T McGonigal
- Department of Neuroscience, Basic Science Building, Medical University of South Carolina, 173 Ashley Avenue, Room 403, Charleston, SC, 29425, USA
| | - K E Nimchuk
- Department of Neuroscience, Basic Science Building, Medical University of South Carolina, 173 Ashley Avenue, Room 403, Charleston, SC, 29425, USA
| | - J T Gass
- Department of Neuroscience, Basic Science Building, Medical University of South Carolina, 173 Ashley Avenue, Room 403, Charleston, SC, 29425, USA.,Department of Biomedical Sciences, James H. Quillen College of Medicine & VA Medical Center, PO Box 70582, Johnson City, TN, 37614, USA
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11
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Smiley CE, Saleh HK, Nimchuk KE, Garcia-Keller C, Gass JT. Adolescent exposure to delta-9-tetrahydrocannabinol and ethanol heightens sensitivity to fear stimuli. Behav Brain Res 2021; 415:113517. [PMID: 34389427 PMCID: PMC8404161 DOI: 10.1016/j.bbr.2021.113517] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 08/02/2021] [Accepted: 08/05/2021] [Indexed: 01/05/2023]
Abstract
Cannabis use disorder (CUD) has doubled in prevalence over the past decade as a nation-wide trend toward legalization allows for increased drug accessibility. As a result, marijuana has become the most commonly used illicit drug in the United States particularly among the adolescent population. This is especially concerning since there is greater risk for the harmful side effects of drug use during this developmental period due to ongoing brain maturation. Increasing evidence indicates that CUD often occurs along with other debilitating conditions including both alcohol use disorder (AUD) and anxiety disorders such post-traumatic stress disorder (PTSD). Additionally, exposure to cannabis, alcohol, and stress can induce alterations in glutamate regulation and homeostasis in the prefrontal cortex (PFC) that may lead to impairments in neuronal functioning and cognition. Therefore, in order to study the relationship between drug exposure and the development of PTSD, these studies utilized rodent models to determine the impact of adolescent exposure to delta-9-tetrahydrocannabinol (THC) and ethanol on responses to fear stimuli during fear conditioning and used calcium imaging to measure glutamate activity in the prelimbic cortex during this behavioral paradigm. The results from these experiments indicate that adolescent exposure to THC and ethanol leads to enhanced sensitivity to fear stimuli both behaviorally and neuronally. Additionally, these effects were attenuated when animals were treated with the glutamatergic modulator N-acetylcysteine (NAC). In summary, these studies support the hypothesis that adolescent exposure to THC and ethanol leads to alterations in fear stimuli processing through glutamatergic reliant modifications in PFC signaling.
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Affiliation(s)
- Cora E Smiley
- Department of Neuroscience, Medical University of South Carolina, Basic Science Building, 173 Ashley Avenue, Room 403, Charleston, SC, 29425, United States.
| | - Heyam K Saleh
- Department of Neuroscience, Medical University of South Carolina, Basic Science Building, 173 Ashley Avenue, Room 403, Charleston, SC, 29425, United States
| | - Katherine E Nimchuk
- Department of Neuroscience, Medical University of South Carolina, Basic Science Building, 173 Ashley Avenue, Room 403, Charleston, SC, 29425, United States
| | - Constanza Garcia-Keller
- Department of Neuroscience, Medical University of South Carolina, Basic Science Building, 173 Ashley Avenue, Room 403, Charleston, SC, 29425, United States
| | - Justin T Gass
- Department of Neuroscience, Medical University of South Carolina, Basic Science Building, 173 Ashley Avenue, Room 403, Charleston, SC, 29425, United States
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12
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Joo YH, Kim JH, Kim HK, Son YD, Cumming P, Kim JH. Functional Analysis of Brain Imaging Suggests Changes in the Availability of mGluR5 and Altered Connectivity in the Cerebral Cortex of Long-Term Abstaining Males with Alcohol Dependence: A Preliminary Study. Life (Basel) 2021; 11:life11060506. [PMID: 34070900 PMCID: PMC8228527 DOI: 10.3390/life11060506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/23/2021] [Accepted: 05/27/2021] [Indexed: 11/16/2022] Open
Abstract
Direct in vivo evidence of altered metabotropic glutamate receptor-5 (mGluR5) availability in alcohol-related disorders is lacking. We performed [11C]ABP688 positron emission tomography (PET) and resting-state functional magnetic resonance imaging (rs-fMRI) in prolonged abstinent subjects with alcohol dependence to examine alterations of mGluR5 availability, and to investigate their functional significance relating to neural systems-level changes. Twelve prolonged abstinent male subjects with alcohol dependence (median abstinence duration: six months) and ten healthy male controls underwent [11C]ABP688 PET imaging and 3-Tesla MRI. For mGluR5 availability, binding potential (BPND) was calculated using the simplified reference tissue model with cerebellar gray matter as the reference region. The initial region-of-interest (ROI)-based analysis yielded no significant group differences in mGluR5 availability. The voxel-based analysis revealed significantly lower [11C]ABP688 BPND in the middle temporal and inferior parietal cortices, and higher BPND in the superior temporal cortex in the alcohol dependence group compared with controls. Functional connectivity analysis of the rs-fMRI data employed seed regions identified from the quantitative [11C]ABP688 PET analysis, which revealed significantly altered functional connectivity from the inferior parietal cortex seed to the occipital pole and dorsal visual cortex in the alcohol dependence group compared with the control group. To our knowledge, this is the first report on the combined analysis of mGluR5 PET imaging and rs-fMRI in subjects with alcohol dependence. These preliminary results suggest the possibility of region-specific alterations of mGluR5 availability in vivo and related functional connectivity perturbations in prolonged abstinent subjects.
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Affiliation(s)
- Yo-Han Joo
- Neuroscience Research Institute, Gachon University, Incheon 21565, Korea; (Y.-H.J.); (J.-H.K.); (H.-K.K.)
| | - Jeong-Hee Kim
- Neuroscience Research Institute, Gachon University, Incheon 21565, Korea; (Y.-H.J.); (J.-H.K.); (H.-K.K.)
- Department of Biomedical Engineering, College of Health Science, Gachon University, Incheon 21936, Korea
| | - Hang-Keun Kim
- Neuroscience Research Institute, Gachon University, Incheon 21565, Korea; (Y.-H.J.); (J.-H.K.); (H.-K.K.)
- Department of Biomedical Engineering, College of Health Science, Gachon University, Incheon 21936, Korea
- Gachon Advanced Institute for Health Science and Technology, Graduate School, Gachon University, Incheon 21565, Korea
| | - Young-Don Son
- Neuroscience Research Institute, Gachon University, Incheon 21565, Korea; (Y.-H.J.); (J.-H.K.); (H.-K.K.)
- Department of Biomedical Engineering, College of Health Science, Gachon University, Incheon 21936, Korea
- Gachon Advanced Institute for Health Science and Technology, Graduate School, Gachon University, Incheon 21565, Korea
- Correspondence: (Y.-D.S.); or (J.-H.K.); Tel.: +82-32-820-4416 (Y.-D.S.); +82-32-460-2696 (J.-H.K.)
| | - Paul Cumming
- Department of Nuclear Medicine, Inselspital, University of Bern, CH-3010 Bern, Switzerland;
- School of Psychology and Counselling, Queensland University of Technology, Brisbane, QLD 4059, Australia
| | - Jong-Hoon Kim
- Neuroscience Research Institute, Gachon University, Incheon 21565, Korea; (Y.-H.J.); (J.-H.K.); (H.-K.K.)
- Gachon Advanced Institute for Health Science and Technology, Graduate School, Gachon University, Incheon 21565, Korea
- Gil Medical Center, Department of Psychiatry, Gachon University College of Medicine, Gachon University, Incheon 21565, Korea
- Correspondence: (Y.-D.S.); or (J.-H.K.); Tel.: +82-32-820-4416 (Y.-D.S.); +82-32-460-2696 (J.-H.K.)
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