It is necessary to find a mechanism that generates first-person inner sensation of pleasure to understand what causes addiction and associated behaviour by drugs of abuse.The actual mechanism is expected to explain se...It is necessary to find a mechanism that generates first-person inner sensation of pleasure to understand what causes addiction and associated behaviour by drugs of abuse.The actual mechanism is expected to explain several disparate findings in nucleus accumbens(NAc),a brain region associated with pleasure,in an interconnected manner.Previously,it was possible to derive a mechanism for natural learning and explain:(1)Generation of inner sensation of memory using changes generated by learning;and(2)Long-term potentiation as an experimental delayed scaled-up change by the same mechanism that occur during natural learning.By extending these findings and by using disparate third person observations in NAc from several studies,present work provides a framework of a mechanism that generates internal sensation of pleasure that can provide interconnected explanations for:(1)Ability to induce robust long-term depression(LTD)in NAc from naïve animals;(2)Impaired ability to induce LTD in“addicted”state;(3)Attenuation of postsynaptic potentials by cocaine;and(4)Reduced firing of medium spiny neurons in response to cocaine or dopamine.Findings made by this work are testable.展开更多
Studies have suggested that the nucleus accumbens(NAc)is implicated in the pathophysiology of major depression;however,the regulatory strategy that targets the NAc to achieve an exclusive and outstanding anti-depressi...Studies have suggested that the nucleus accumbens(NAc)is implicated in the pathophysiology of major depression;however,the regulatory strategy that targets the NAc to achieve an exclusive and outstanding anti-depression benefit has not been elucidated.Here,we identified a specific reduction of cyclic adenosine monophosphate(cAMP)in the subset of dopamine D1 receptor medium spiny neurons(D1-MSNs)in the NAc that promoted stress susceptibility,while the stimulation of cAMP production in NAc D1-MSNs efficiently rescued depression-like behaviors.Ketamine treatment enhanced cAMP both in D1-MSNs and dopamine D2 receptor medium spiny neurons(D2-MSNs)of depressed mice,however,the rapid antidepressant effect of ketamine solely depended on elevating cAMP in NAc D1-MSNs.We discovered that a higher dose of crocin markedly increased cAMP in the NAc and consistently relieved depression 24 h after oral administration,but not a lower dose.The fast onset property of crocin was verified through multicenter studies.Moreover,crocin specifically targeted at D1-MSN cAMP signaling in the NAc to relieve depression and had no effect on D2-MSN.These findings characterize a new strategy to achieve an exclusive and outstanding anti-depression benefit by elevating cAMP in D1-MSNs in the NAc,and provide a potential rapid antidepressant drug candidate,crocin.展开更多
Adverse experiences in early life have long-lasting negative impacts on behavior and the brain in adulthood,one of which is sleep disturbance.As the corticotropin-releasing hormone(CRH)–corticotropin-releasing hormon...Adverse experiences in early life have long-lasting negative impacts on behavior and the brain in adulthood,one of which is sleep disturbance.As the corticotropin-releasing hormone(CRH)–corticotropin-releasing hormone receptor 1(CRHR1)system and nucleus accumbens(NAc)play important roles in both stress responses and sleep-wake regulation,in this study we investigated whether the NAc CRH–CRHR1 system mediates early-life stress-induced abnormalities in sleep-wake behavior in adult mice.Using the limited nesting and bedding material paradigm from postnatal days 2 to 9,we found that early-life stress disrupted sleep-wake behaviors during adulthood,including increased wakefulness and decreased non-rapid eye movement(NREM)sleep time during the dark period and increased rapid eye movement(REM)sleep time during the light period.The stress-induced sleep disturbances were accompanied by dendritic atrophy in the NAc and both were largely reversed by daily systemic administration of the CRHR1 antagonist antalarmin during stress exposure.Importantly,Crh overexpression in the NAc reproduced the effects of early-life stress on sleep-wake behavior and NAc morphology,whereas NAc Crhr1 knockdown reversed these effects(including increased wakefulness and reduced NREM sleep in the dark period and NAc dendritic atrophy).Together,our findings demonstrate the negative influence of early-life stress on sleep architecture and the structural plasticity of the NAc,and highlight the critical role of the NAc CRH–CRHR1 system in modulating these negative outcomes evoked by early-life stress.展开更多
The nucleus accumbens shell(NAcSh) plays an important role in reward and aversion. Traditionally, NAc dopamine receptor 2-expressing(D2) neurons are assumed to function in aversion. However, this has been challenged b...The nucleus accumbens shell(NAcSh) plays an important role in reward and aversion. Traditionally, NAc dopamine receptor 2-expressing(D2) neurons are assumed to function in aversion. However, this has been challenged by recent reports which attribute positive motivational roles to D2 neurons. Using optogenetics and multiple behavioral tasks, we found that activation of D2 neurons in the dorsomedial NAcSh drives preference and increases the motivation for rewards, whereas activation of ventral NAcSh D2 neurons induces aversion. Stimulation of D2 neurons in the ventromedial NAcSh increases movement speed and stimulation of D2 neurons in the ventrolateral NAc Sh decreases movement speed. Combining retrograde tracing and in situ hybridization, we demonstrated that glutamatergic and GABAergic neurons in the ventral pallidum receive inputs differentially from the dorsomedial and ventral NAcSh. All together, these findings shed light on the controversy regarding the function of NAcSh D2 neurons, and provide new insights into understanding the heterogeneity of the NAcSh.展开更多
Ultrasound stimulation is an emerging noninvasive option in treating neuropsychiatric disorders. The present study investigates the behavioral alterations resulting from ultrasound stimulation on the nucleus accumbens...Ultrasound stimulation is an emerging noninvasive option in treating neuropsychiatric disorders. The present study investigates the behavioral alterations resulting from ultrasound stimulation on the nucleus accumbens(NAc) in freely moving mice. Our results show that an acute ultrasound stimulation on the NAc, rather than the visual cortex or auditory cortex, led to a pronounced avoidance behavior, while repeated NAc ultrasound stimulation resulted in an obvious conditioned place aversion with changes in synaptic protein(Glu A1/2 subunit) expression. Notably, NAc ultrasound stimulation suppressed the morphine-induced conditioned place preference. The results provide evidence that NAc ultrasound stimulation can be applied as a potential noninvasive therapeutic option in treating psychiatric disorders.展开更多
The medium spiny neurons(MSNs)in the nucleus accumbens(NAc)integrate excitatory and inhibitory synaptic inputs and gate motivational and emotional behavior output.Here we report that the relative intensity of excitato...The medium spiny neurons(MSNs)in the nucleus accumbens(NAc)integrate excitatory and inhibitory synaptic inputs and gate motivational and emotional behavior output.Here we report that the relative intensity of excitatory and inhibitory synaptic inputs to MSNs of the NAc shell was decreased in mice with neuropathic pain induced by spinal nerve ligation(SNL).SNL increased the frequency,but not the amplitude of spontaneous inhibitory postsynaptic currents(sIPSCs),and decreased both the frequency and amplitude of spontaneous excitatory postsynaptic currents(sEPSCs)in the MSNs.SNL also decreased the paired-pulse ratio(PPR)of evoked IPSCs but increased the PPR of evoked EPSCs.Moreover,acute bath application of C–C motif chemokine ligand 2(CCL2)increased the frequency and amplitude of sIPSCs and sEPSCs in the MSNs,and especially strengthened the amplitude of N-methyl-D-aspartate receptor(NMDAR)-mediated miniature EPSCs.Further Ccl2 overexpression in the NAc in vivo decreased the peak amplitude of the sEPSC/sIPSC ratio.Finally,Ccr2 knock-down improved the impaired induction of NMDAR-dependent long-term depression(LTD)in the NAc after SNL.These results suggest that CCL2/CCR2 signaling plays a role in the integration of excitatory/inhibitory synaptic transmission and leads to an increase of the LTD induction threshold at the synapses of MSNs during neuropathic pain.展开更多
A strong animal survival instinct is to approach objects and situations that are of benefit and to avoid risk.In humans,a large proportion of mental disorders are accompanied by impairments in risk avoidance.One of th...A strong animal survival instinct is to approach objects and situations that are of benefit and to avoid risk.In humans,a large proportion of mental disorders are accompanied by impairments in risk avoidance.One of the most important genes involved in mental disorders is disrupted-in-schizophrenia-1(DISC1),and animal models in which this gene has some level of dysfunction show emotion-related impairments.However,it is not known whether DISC1 mouse models have an impairment in avoiding potential risks.In the present study,we used DISC1-N terminal truncation(DISC1-N^(TM))mice to investigate risk avoidance and found that these mice were impaired in risk avoidance on the elevated plus maze(EPM)and showed reduced social preference in a three-chamber social interaction test.Following EPM tests,c-Fos expression levels indicated that the nucleus accumbens(NAc)was associated with risk-avoidance behavior in DISC1-N^(TM)mice.In addition,in vivo electrophysiological recordings following tamoxifen administration showed that the firing rates of fast-spiking neurons(FS)in the NAc were significantly lower in DISC1-N^(TM)mice than in wild-type(WT)mice.In addition,in vitro patch clamp recording revealed that the frequency of action potentials stimulated by current injection was lower in parvalbumin(PV)neurons in the NAc of DISC1-N^(TM)mice than in WT controls.The impairment of risk avoidance in DISC1-N^(TM)mice was rescued using optogenetic tools that activated NAcPV neurons.Finally,inhibition of the activity of NAcPV neurons in PV-Cre mice mimicked the risk-avoidance impairment found in DISC1-N^(TM)mice during tests on the elevated zero maze.Taken together,our findings confirm an impairment in risk avoidance in DISC1-N^(TM)mice and suggest that reduced excitability of NAc^(PV) neurons is responsible.展开更多
Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral response.Recent studies have shown that brain-derived neurotrophic factor expression in stressed mice ...Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral response.Recent studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and hippocampus.Determining how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress psychopathology.In this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of depression.We focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine circuit.We determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic system.Therefore,BDNF might be a biological indicator regulating stress-related processes in various brain regions.展开更多
A significant amount of evidence indicates that micro RNAs(mi RNAs) play an important role in drug addiction. The nucleus accumbens(NAc) is a critical part of the brain's reward circuit and is involved in a variet...A significant amount of evidence indicates that micro RNAs(mi RNAs) play an important role in drug addiction. The nucleus accumbens(NAc) is a critical part of the brain's reward circuit and is involved in a variety of psychiatric disorders, including depression, anxiety, and drug addiction. However, few studies have examined the expression of mi RNAs and their functional roles in the NAc under conditions of morphine addiction. In this study, mice were intravenously infused with morphine(0.01, 0.03, 0.3, 1 and 3 mg/kg/infusion) and showed inverted U-shaped response. After morphine self-administration, NAc was used to analyze the functional networks of altered mi RNAs and their putative target m RNAs in the NAc following intravenous self-administration of morphine. We utilized several bioinformatics tools, including Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway mapping and Cy Target Linker. We found that 62 mi RNAs were altered and exhibited differential expression patterns. The putative targets were related to diverse regulatory functions, such as neurogenesis, neurodegeneration, and synaptic plasticity, as well as the pharmacological effects of morphine(receptor internalization/endocytosis). The present findings provide novel insights into the regulatory mechanisms of accumbal molecules under conditions of morphine addiction and identify several novel biomarkers associated with morphine addiction.展开更多
OBJECTIVE To examine the effects of aquaporin 4(AQP4) on opioid addiction and underlie the mechanism behind it. METHODS(1) In the heroin-induced self-administration(SA) experiment,we explored the role of AQP4 on heroi...OBJECTIVE To examine the effects of aquaporin 4(AQP4) on opioid addiction and underlie the mechanism behind it. METHODS(1) In the heroin-induced self-administration(SA) experiment,we explored the role of AQP4 on heroin-induced psychological addiction. After the mice were trained to learn heroin-induced SA under a fixedratio1(FR1) reinforcement program for 7 d,we randomly switched the heroin doses to 0.00625,0.0125,0.025,0.05 or 0.1 mg·kg^(-1)per infusion to counterbalance assignment design. In the end,all mice underwent extinction training and reinstatement testing.(2) In oral sucrose self-administration,5% sucrose solution was used for the mice and the procedures were similar to heroin SA.(3) In morphine-induced hyperactivity test,mice were habituated in the test apparatus for 30 min and then were given saline(10 mL·kg^(-1),sc) or morphine(10 or 20 mg·kg^(-1),sc) to record the locomotion for 1.5 h.(4) For the in vivo microdialysis experiment,mice were surgically implanted with intracranial guide cannula into nucleus accumbens(AP +1.4 mm,ML ±0.9 mm,DV-3.8 mm from bregma). After 5 d of recovery from surgery,the mice were challenged by saline(10 mL·kg^(-1),sc)or morphine(10 mg·kg^(-1),sc),and then samples were collected every 20 min. RESULTS We found that AQP4 deletion had no effects on sucrose-seeking and sucrose-taking,but it significantly attenuated heroin-taking and heroin-seeking behaviors in heroin self-administration. Besides these,AQP4 deletion had no effects on basal level of locomotion,but dramatically decreased morphine-induced hyperactivity.Furthermore,the in vivo microdialysis studies showed that AQP4 deficiency inhibited morphine(10mg · kg^(-1),sc)-induced elevation of extracellular dopamine levels in nucleus accumbens in mice.CONCLUSION Our present findings demonstrate that AQP4 was potentially involved in the properties of opioid rewarding by inhibiting dopamine release in nucleus accumbens(NAc).展开更多
The mesolimbic dopamine system consisting of dopaminergic neurons projecting from the ventral tegmental area (VTA) to the nucleus accumbens (N.Acc.) mediates the reinforcing effects of addictive drugs including alcoho...The mesolimbic dopamine system consisting of dopaminergic neurons projecting from the ventral tegmental area (VTA) to the nucleus accumbens (N.Acc.) mediates the reinforcing effects of addictive drugs including alcohol. Given that VTA is a heterogeneous area and that alcohol, in rather low doses, interacts directly with ligand-gated ion channels, we hypothesised that low, rather than high, doses of alcohol into the VTA activate the mesolimbic dopamine system and that alcohol may have different effects in the anterior and posterior parts of the VTA. The present study was undertaken to investigate this hypothesis. The present series of experiment show that infusion of a low dose of alcohol (20 mM) into the anterior, but not posterior, part of the VTA increases accumbal dopamine release in rats. In addition, higher doses of alcohol (100 or 300 mM) into the anterior or posterior part of the VTA do not affect the release of dopamine in the N.Acc., suggesting that low doses of alcohol can activate the mesolimbic dopamine system via mechanisms in the VTA. These data contribute to understanding the neuronal mechanisms underlying the dependence-producing properties of alcohol and could tentatively contribute to that new treatment strategies for alcohol use disorder can be developed.展开更多
Methcathinone(MCAT)belongs to the designer drugs called synthetic cathinones,which are abused worldwide for recreational purposes.It has strong stimulant effects,including enhanced euphoria,sensation,alertness,and emp...Methcathinone(MCAT)belongs to the designer drugs called synthetic cathinones,which are abused worldwide for recreational purposes.It has strong stimulant effects,including enhanced euphoria,sensation,alertness,and empathy.However,little is known about how MCAT modulates neuronal activity in vivo.Here,we evaluated the effect of MCAT on neuronal activity with a series of functional approaches.C-Fos immunostaining showed that MCAT increased the number of activated neurons by 6-fold,especially in sensory and motor cortices,striatum,and midbrain motor nuclei.In vivo single-unit recording and two-photon Ca^(2+) imaging revealed that a large proportion of neurons increased spiking activity upon MCAT administration.Notably,MCAT induced a strong de-correlation of population activity and increased trial-to-trial reliability,specifically during a natural movie stimulus.It improved the information-processing efficiency by enhancing the single-neuron coding capacity,suggesting a cortical network mechanism of the enhanced perception produced by psychoactive stimulants.展开更多
Preoperative sleep loss can amplify post-operative mechanical hyperalgesia.However,the underlying mechanisms are still largely unknown.In the current study,rats were randomly allocated to a control group and an acute ...Preoperative sleep loss can amplify post-operative mechanical hyperalgesia.However,the underlying mechanisms are still largely unknown.In the current study,rats were randomly allocated to a control group and an acute sleep deprivation(ASD)group which experienced 6 h ASD before surgery.Then the variations in cerebral function and activity were investigated with multi-modal techniques,such as nuclear magnetic resonance,functional magnetic resonance imaging,c-Fos immunofluorescence,and electrophysiology.The results indicated that ASD induced hyperalgesia,and the metabolic kinetics were remarkably decreased in the striatum and midbrain.The functional connectivity(FC)between the nucleus accumbens(NAc,a subregion of the ventral striatum)and the ventrolateral periaqueductal gray(vLPAG)was significantly reduced,and the c-Fos expression in the NAc and the vLPAG was suppressed.Furthermore,the electrophysiological recordings demonstrated that both the neuronal activity in the NAc and the vLPAG,and the coherence of the NAc-vLPAG were suppressed in both resting and task states.This study showed that neuronal activity in the NAc and the vLPAG were weakened and the FC between the NAc and the vLPAG was also suppressed in rats with ASD-induced hyperalgesia.This study highlights the importance of preoperative sleep management for surgical patients.展开更多
文摘It is necessary to find a mechanism that generates first-person inner sensation of pleasure to understand what causes addiction and associated behaviour by drugs of abuse.The actual mechanism is expected to explain several disparate findings in nucleus accumbens(NAc),a brain region associated with pleasure,in an interconnected manner.Previously,it was possible to derive a mechanism for natural learning and explain:(1)Generation of inner sensation of memory using changes generated by learning;and(2)Long-term potentiation as an experimental delayed scaled-up change by the same mechanism that occur during natural learning.By extending these findings and by using disparate third person observations in NAc from several studies,present work provides a framework of a mechanism that generates internal sensation of pleasure that can provide interconnected explanations for:(1)Ability to induce robust long-term depression(LTD)in NAc from naïve animals;(2)Impaired ability to induce LTD in“addicted”state;(3)Attenuation of postsynaptic potentials by cocaine;and(4)Reduced firing of medium spiny neurons in response to cocaine or dopamine.Findings made by this work are testable.
基金supported by National Natural Science Foundation of China(No.82104278)Leading Technology Foundation Research Project of Jiangsu Province(No.BK20192005,China)+4 种基金National Key Project of Science and Technology for Innovation Drugs of China(No.2017ZX09301013)CAMS Innovation Fund for Medical Sciences(CIFMS,No.2021-I2M-5-011,China)Sanming Project of Medicine in Shenzhen(No.SZSM201801060,China)Project of State Key Laboratory of Natural Medicines,China Pharmaceutical University(No.SKLNMKF202203,China)National Innovation and Entrepreneurship Training Program for Undergraduate,China Pharmaceutical University(Nos.2023103161381 and 2023103161287,China)。
文摘Studies have suggested that the nucleus accumbens(NAc)is implicated in the pathophysiology of major depression;however,the regulatory strategy that targets the NAc to achieve an exclusive and outstanding anti-depression benefit has not been elucidated.Here,we identified a specific reduction of cyclic adenosine monophosphate(cAMP)in the subset of dopamine D1 receptor medium spiny neurons(D1-MSNs)in the NAc that promoted stress susceptibility,while the stimulation of cAMP production in NAc D1-MSNs efficiently rescued depression-like behaviors.Ketamine treatment enhanced cAMP both in D1-MSNs and dopamine D2 receptor medium spiny neurons(D2-MSNs)of depressed mice,however,the rapid antidepressant effect of ketamine solely depended on elevating cAMP in NAc D1-MSNs.We discovered that a higher dose of crocin markedly increased cAMP in the NAc and consistently relieved depression 24 h after oral administration,but not a lower dose.The fast onset property of crocin was verified through multicenter studies.Moreover,crocin specifically targeted at D1-MSN cAMP signaling in the NAc to relieve depression and had no effect on D2-MSN.These findings characterize a new strategy to achieve an exclusive and outstanding anti-depression benefit by elevating cAMP in D1-MSNs in the NAc,and provide a potential rapid antidepressant drug candidate,crocin.
基金supported by the National Key Basic Research Program of China(973 Program,2015CB856401)the Beijing National Science Foundation(7222236)+1 种基金the Capital Medical Development Research Fund(2020-2-4113)the National Natural Science Foundation of China(81630031,81771468,82071528,and 82171529).
文摘Adverse experiences in early life have long-lasting negative impacts on behavior and the brain in adulthood,one of which is sleep disturbance.As the corticotropin-releasing hormone(CRH)–corticotropin-releasing hormone receptor 1(CRHR1)system and nucleus accumbens(NAc)play important roles in both stress responses and sleep-wake regulation,in this study we investigated whether the NAc CRH–CRHR1 system mediates early-life stress-induced abnormalities in sleep-wake behavior in adult mice.Using the limited nesting and bedding material paradigm from postnatal days 2 to 9,we found that early-life stress disrupted sleep-wake behaviors during adulthood,including increased wakefulness and decreased non-rapid eye movement(NREM)sleep time during the dark period and increased rapid eye movement(REM)sleep time during the light period.The stress-induced sleep disturbances were accompanied by dendritic atrophy in the NAc and both were largely reversed by daily systemic administration of the CRHR1 antagonist antalarmin during stress exposure.Importantly,Crh overexpression in the NAc reproduced the effects of early-life stress on sleep-wake behavior and NAc morphology,whereas NAc Crhr1 knockdown reversed these effects(including increased wakefulness and reduced NREM sleep in the dark period and NAc dendritic atrophy).Together,our findings demonstrate the negative influence of early-life stress on sleep architecture and the structural plasticity of the NAc,and highlight the critical role of the NAc CRH–CRHR1 system in modulating these negative outcomes evoked by early-life stress.
基金supported by National Science Foundation of China grants 31571095 and 91332122a Key Scientific Technological Innovation Research project from the Ministry of Education+1 种基金a grant from Insitute Guo Qiang at Tsinghua Universityfunding from the Beijing Program on the Study of Functional Chips and Related Core Technologies of Brain-inspired Computing Systems。
文摘The nucleus accumbens shell(NAcSh) plays an important role in reward and aversion. Traditionally, NAc dopamine receptor 2-expressing(D2) neurons are assumed to function in aversion. However, this has been challenged by recent reports which attribute positive motivational roles to D2 neurons. Using optogenetics and multiple behavioral tasks, we found that activation of D2 neurons in the dorsomedial NAcSh drives preference and increases the motivation for rewards, whereas activation of ventral NAcSh D2 neurons induces aversion. Stimulation of D2 neurons in the ventromedial NAcSh increases movement speed and stimulation of D2 neurons in the ventrolateral NAc Sh decreases movement speed. Combining retrograde tracing and in situ hybridization, we demonstrated that glutamatergic and GABAergic neurons in the ventral pallidum receive inputs differentially from the dorsomedial and ventral NAcSh. All together, these findings shed light on the controversy regarding the function of NAcSh D2 neurons, and provide new insights into understanding the heterogeneity of the NAcSh.
基金supported by the National Natural Science Foundation of China(81527901,81822017,11534013,11774371,31771215)Youth Innovation Promotion Association CAS(2018393)+1 种基金sponsored by the Science and Technology Commission of Shanghai Municipality(18QA1403700,18JC1420304,18140901700)Shanghai Clinical Research Center for Mental Health(19MC1911100)。
文摘Ultrasound stimulation is an emerging noninvasive option in treating neuropsychiatric disorders. The present study investigates the behavioral alterations resulting from ultrasound stimulation on the nucleus accumbens(NAc) in freely moving mice. Our results show that an acute ultrasound stimulation on the NAc, rather than the visual cortex or auditory cortex, led to a pronounced avoidance behavior, while repeated NAc ultrasound stimulation resulted in an obvious conditioned place aversion with changes in synaptic protein(Glu A1/2 subunit) expression. Notably, NAc ultrasound stimulation suppressed the morphine-induced conditioned place preference. The results provide evidence that NAc ultrasound stimulation can be applied as a potential noninvasive therapeutic option in treating psychiatric disorders.
基金Grants from the National Natural Science Foundation of China(32030048,31871064,and 31671091).
文摘The medium spiny neurons(MSNs)in the nucleus accumbens(NAc)integrate excitatory and inhibitory synaptic inputs and gate motivational and emotional behavior output.Here we report that the relative intensity of excitatory and inhibitory synaptic inputs to MSNs of the NAc shell was decreased in mice with neuropathic pain induced by spinal nerve ligation(SNL).SNL increased the frequency,but not the amplitude of spontaneous inhibitory postsynaptic currents(sIPSCs),and decreased both the frequency and amplitude of spontaneous excitatory postsynaptic currents(sEPSCs)in the MSNs.SNL also decreased the paired-pulse ratio(PPR)of evoked IPSCs but increased the PPR of evoked EPSCs.Moreover,acute bath application of C–C motif chemokine ligand 2(CCL2)increased the frequency and amplitude of sIPSCs and sEPSCs in the MSNs,and especially strengthened the amplitude of N-methyl-D-aspartate receptor(NMDAR)-mediated miniature EPSCs.Further Ccl2 overexpression in the NAc in vivo decreased the peak amplitude of the sEPSC/sIPSC ratio.Finally,Ccr2 knock-down improved the impaired induction of NMDAR-dependent long-term depression(LTD)in the NAc after SNL.These results suggest that CCL2/CCR2 signaling plays a role in the integration of excitatory/inhibitory synaptic transmission and leads to an increase of the LTD induction threshold at the synapses of MSNs during neuropathic pain.
基金This work was supported by the National Natural Science Foundation of China(31671116,31761163005,31800881,and 91132306)the International Big Science Program Cultivation Project of Chinese Academy of Sciences(172644KYS820170004)+3 种基金the External Cooperation Program of the Chinese Academy of Sciences(172644KYSB20160057)Science and Technology Program of Guangzhou Municipality(202007030001)the Key-Area Research and Development Program of Guangdong Province(2018B030331001 and 2018B03033600)Shenzhen Government Basic Research Grants(JCYJ20200109115405930 and JCYJ20200109150717745).
文摘A strong animal survival instinct is to approach objects and situations that are of benefit and to avoid risk.In humans,a large proportion of mental disorders are accompanied by impairments in risk avoidance.One of the most important genes involved in mental disorders is disrupted-in-schizophrenia-1(DISC1),and animal models in which this gene has some level of dysfunction show emotion-related impairments.However,it is not known whether DISC1 mouse models have an impairment in avoiding potential risks.In the present study,we used DISC1-N terminal truncation(DISC1-N^(TM))mice to investigate risk avoidance and found that these mice were impaired in risk avoidance on the elevated plus maze(EPM)and showed reduced social preference in a three-chamber social interaction test.Following EPM tests,c-Fos expression levels indicated that the nucleus accumbens(NAc)was associated with risk-avoidance behavior in DISC1-N^(TM)mice.In addition,in vivo electrophysiological recordings following tamoxifen administration showed that the firing rates of fast-spiking neurons(FS)in the NAc were significantly lower in DISC1-N^(TM)mice than in wild-type(WT)mice.In addition,in vitro patch clamp recording revealed that the frequency of action potentials stimulated by current injection was lower in parvalbumin(PV)neurons in the NAc of DISC1-N^(TM)mice than in WT controls.The impairment of risk avoidance in DISC1-N^(TM)mice was rescued using optogenetic tools that activated NAcPV neurons.Finally,inhibition of the activity of NAcPV neurons in PV-Cre mice mimicked the risk-avoidance impairment found in DISC1-N^(TM)mice during tests on the elevated zero maze.Taken together,our findings confirm an impairment in risk avoidance in DISC1-N^(TM)mice and suggest that reduced excitability of NAc^(PV) neurons is responsible.
基金supported financially by the National Natural Science Foundation of China,No.82071272(to YZ).
文摘Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral response.Recent studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and hippocampus.Determining how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress psychopathology.In this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of depression.We focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine circuit.We determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic system.Therefore,BDNF might be a biological indicator regulating stress-related processes in various brain regions.
基金funded by the National Research Council of Science & Technology(NST)grant by the Korean government(MSIP)(No.CRC-15-04-KIST)the National Research Foundation of Korea under the grant(No.NRF-2017R1A2B200399Mid-career Researcher Program)
文摘A significant amount of evidence indicates that micro RNAs(mi RNAs) play an important role in drug addiction. The nucleus accumbens(NAc) is a critical part of the brain's reward circuit and is involved in a variety of psychiatric disorders, including depression, anxiety, and drug addiction. However, few studies have examined the expression of mi RNAs and their functional roles in the NAc under conditions of morphine addiction. In this study, mice were intravenously infused with morphine(0.01, 0.03, 0.3, 1 and 3 mg/kg/infusion) and showed inverted U-shaped response. After morphine self-administration, NAc was used to analyze the functional networks of altered mi RNAs and their putative target m RNAs in the NAc following intravenous self-administration of morphine. We utilized several bioinformatics tools, including Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway mapping and Cy Target Linker. We found that 62 mi RNAs were altered and exhibited differential expression patterns. The putative targets were related to diverse regulatory functions, such as neurogenesis, neurodegeneration, and synaptic plasticity, as well as the pharmacological effects of morphine(receptor internalization/endocytosis). The present findings provide novel insights into the regulatory mechanisms of accumbal molecules under conditions of morphine addiction and identify several novel biomarkers associated with morphine addiction.
文摘OBJECTIVE To examine the effects of aquaporin 4(AQP4) on opioid addiction and underlie the mechanism behind it. METHODS(1) In the heroin-induced self-administration(SA) experiment,we explored the role of AQP4 on heroin-induced psychological addiction. After the mice were trained to learn heroin-induced SA under a fixedratio1(FR1) reinforcement program for 7 d,we randomly switched the heroin doses to 0.00625,0.0125,0.025,0.05 or 0.1 mg·kg^(-1)per infusion to counterbalance assignment design. In the end,all mice underwent extinction training and reinstatement testing.(2) In oral sucrose self-administration,5% sucrose solution was used for the mice and the procedures were similar to heroin SA.(3) In morphine-induced hyperactivity test,mice were habituated in the test apparatus for 30 min and then were given saline(10 mL·kg^(-1),sc) or morphine(10 or 20 mg·kg^(-1),sc) to record the locomotion for 1.5 h.(4) For the in vivo microdialysis experiment,mice were surgically implanted with intracranial guide cannula into nucleus accumbens(AP +1.4 mm,ML ±0.9 mm,DV-3.8 mm from bregma). After 5 d of recovery from surgery,the mice were challenged by saline(10 mL·kg^(-1),sc)or morphine(10 mg·kg^(-1),sc),and then samples were collected every 20 min. RESULTS We found that AQP4 deletion had no effects on sucrose-seeking and sucrose-taking,but it significantly attenuated heroin-taking and heroin-seeking behaviors in heroin self-administration. Besides these,AQP4 deletion had no effects on basal level of locomotion,but dramatically decreased morphine-induced hyperactivity.Furthermore,the in vivo microdialysis studies showed that AQP4 deficiency inhibited morphine(10mg · kg^(-1),sc)-induced elevation of extracellular dopamine levels in nucleus accumbens in mice.CONCLUSION Our present findings demonstrate that AQP4 was potentially involved in the properties of opioid rewarding by inhibiting dopamine release in nucleus accumbens(NAc).
基金grants from the Swedish Research Council (grant no. K2006-21X-04247-33-3 and 2009-2782)The Swedish brain foundation, LUA/ALF (grant no. 148251)
文摘The mesolimbic dopamine system consisting of dopaminergic neurons projecting from the ventral tegmental area (VTA) to the nucleus accumbens (N.Acc.) mediates the reinforcing effects of addictive drugs including alcohol. Given that VTA is a heterogeneous area and that alcohol, in rather low doses, interacts directly with ligand-gated ion channels, we hypothesised that low, rather than high, doses of alcohol into the VTA activate the mesolimbic dopamine system and that alcohol may have different effects in the anterior and posterior parts of the VTA. The present study was undertaken to investigate this hypothesis. The present series of experiment show that infusion of a low dose of alcohol (20 mM) into the anterior, but not posterior, part of the VTA increases accumbal dopamine release in rats. In addition, higher doses of alcohol (100 or 300 mM) into the anterior or posterior part of the VTA do not affect the release of dopamine in the N.Acc., suggesting that low doses of alcohol can activate the mesolimbic dopamine system via mechanisms in the VTA. These data contribute to understanding the neuronal mechanisms underlying the dependence-producing properties of alcohol and could tentatively contribute to that new treatment strategies for alcohol use disorder can be developed.
基金supported by the National Natural Science Foundation of China(31871089 and 31871028)Junior Thousand Talents Program of China,Fundamental Research Funds for the Central Universities(HUST:2172019kfyXKJC077 and HUST:2172019kfyRCPY064)Key Laboratory of Forensic Toxicology,Ministry of Public Security of China(Beijing Municipal Public Security Bureau:2020FTDWFX02 and 2019FTDWFX06).
文摘Methcathinone(MCAT)belongs to the designer drugs called synthetic cathinones,which are abused worldwide for recreational purposes.It has strong stimulant effects,including enhanced euphoria,sensation,alertness,and empathy.However,little is known about how MCAT modulates neuronal activity in vivo.Here,we evaluated the effect of MCAT on neuronal activity with a series of functional approaches.C-Fos immunostaining showed that MCAT increased the number of activated neurons by 6-fold,especially in sensory and motor cortices,striatum,and midbrain motor nuclei.In vivo single-unit recording and two-photon Ca^(2+) imaging revealed that a large proportion of neurons increased spiking activity upon MCAT administration.Notably,MCAT induced a strong de-correlation of population activity and increased trial-to-trial reliability,specifically during a natural movie stimulus.It improved the information-processing efficiency by enhancing the single-neuron coding capacity,suggesting a cortical network mechanism of the enhanced perception produced by psychoactive stimulants.
基金This work was supported by grants from the National Natural Science Foundation of China(82071208,81870851,31771193,and 81971775)the Outstanding Talented Young Doctor Program of Hubei Province(HB20200407)+2 种基金the Translational Medicine,and interdisciplinary Research Joint Fund of Zhongnan Hospital of Wuhan University(ZNJC202012)the Medical Sci-Tech Innovation Platform of Zhongnan Hospital of Wuhan Universitythe Strategic Priority Research Program of the Chinese Academy of Sciences(XDB32030200).
文摘Preoperative sleep loss can amplify post-operative mechanical hyperalgesia.However,the underlying mechanisms are still largely unknown.In the current study,rats were randomly allocated to a control group and an acute sleep deprivation(ASD)group which experienced 6 h ASD before surgery.Then the variations in cerebral function and activity were investigated with multi-modal techniques,such as nuclear magnetic resonance,functional magnetic resonance imaging,c-Fos immunofluorescence,and electrophysiology.The results indicated that ASD induced hyperalgesia,and the metabolic kinetics were remarkably decreased in the striatum and midbrain.The functional connectivity(FC)between the nucleus accumbens(NAc,a subregion of the ventral striatum)and the ventrolateral periaqueductal gray(vLPAG)was significantly reduced,and the c-Fos expression in the NAc and the vLPAG was suppressed.Furthermore,the electrophysiological recordings demonstrated that both the neuronal activity in the NAc and the vLPAG,and the coherence of the NAc-vLPAG were suppressed in both resting and task states.This study showed that neuronal activity in the NAc and the vLPAG were weakened and the FC between the NAc and the vLPAG was also suppressed in rats with ASD-induced hyperalgesia.This study highlights the importance of preoperative sleep management for surgical patients.
