1
|
Borzou A, Miller SN, Hommel JD, Schwarz JM. Cocaine diminishes functional network robustness and destabilizes the energy landscape of neuronal activity in the medial prefrontal cortex. PNAS NEXUS 2024; 3:pgae092. [PMID: 38476665 PMCID: PMC10929585 DOI: 10.1093/pnasnexus/pgae092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Accepted: 02/13/2024] [Indexed: 03/14/2024]
Abstract
We present analysis of neuronal activity recordings from a subset of neurons in the medial prefrontal cortex of rats before and after the administration of cocaine. Using an underlying modern Hopfield model as a description for the neuronal network, combined with a machine learning approach, we compute the underlying functional connectivity of the neuronal network. We find that the functional connectivity changes after the administration of cocaine with both functional-excitatory and functional-inhibitory neurons being affected. Using conventional network analysis, we find that the diameter of the graph, or the shortest length between the two most distant nodes, increases with cocaine, suggesting that the neuronal network is less robust. We also find that the betweenness centrality scores for several of the functional-excitatory and functional-inhibitory neurons decrease significantly, while other scores remain essentially unchanged, to also suggest that the neuronal network is less robust. Finally, we study the distribution of neuronal activity and relate it to energy to find that cocaine drives the neuronal network towards destabilization in the energy landscape of neuronal activation. While this destabilization is presumably temporary given one administration of cocaine, perhaps this initial destabilization indicates a transition towards a new stable state with repeated cocaine administration. However, such analyses are useful more generally to understand how neuronal networks respond to perturbations.
Collapse
Affiliation(s)
- Ahmad Borzou
- Department of Physics and BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA
- CompuFlair, Houston, TX 77064, USA
| | - Sierra N Miller
- Department of Pharmacology and Toxicology, Center for Addiction Sciences and Therapeutics, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Jonathan D Hommel
- Department of Pharmacology and Toxicology, Center for Addiction Sciences and Therapeutics, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - J M Schwarz
- Department of Physics and BioInspired Institute, Syracuse University, Syracuse, NY 13244, USA
- Indian Creek Farm, Ithaca, NY 14850, USA
| |
Collapse
|
2
|
Wang L, Gao M, Wang Q, Sun L, Younus M, Ma S, Liu C, Shi L, Lu Y, Zhou B, Sun S, Chen G, Li J, Zhang Q, Zhu F, Wang C, Zhou Z. Cocaine induces locomotor sensitization through a dopamine-dependent VTA-mPFC-FrA cortico-cortical pathway in male mice. Nat Commun 2023; 14:1568. [PMID: 36944634 PMCID: PMC10030897 DOI: 10.1038/s41467-023-37045-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 02/28/2023] [Indexed: 03/23/2023] Open
Abstract
As a central part of the mammalian brain, the prefrontal cortex (PFC) has been implicated in regulating cocaine-induced behaviors including compulsive seeking and reinstatement. Although dysfunction of the PFC has been reported in animal and human users with chronic cocaine abuse, less is known about how the PFC is involved in cocaine-induced behaviors. By using two-photon Ca2+ imaging to simultaneously record tens of intact individual networking neurons in the frontal association cortex (FrA) in awake male mice, here we report that a systematic acute cocaine exposure decreased the FrA neural activity in mice, while the chemogenetic intervention blocked the cocaine-induced locomotor sensitization. The hypoactivity of FrA neurons was critically dependent on both dopamine transporters and dopamine transmission in the ventromedial PFC (vmPFC). Both dopamine D1R and D2R neurons in the vmPFC projected to and innervated FrA neurons, the manipulation of which changed the cocaine-induced hypoactivity of the FrA and locomotor sensitization. Together, this work demonstrates acute cocaine-induced hypoactivity of FrA neurons in awake mice, which defines a cortico-cortical projection bridging dopamine transmission and cocaine sensitization.
Collapse
Affiliation(s)
- Lun Wang
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Min Gao
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
- Joint Graduate Program of Peking-Tsinghua-NIBS, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China
| | - Qinglong Wang
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Liyuan Sun
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Muhammad Younus
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Sixing Ma
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Can Liu
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Li Shi
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Yang Lu
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Bo Zhou
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Suhua Sun
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Guoqing Chen
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Jie Li
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Quanfeng Zhang
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China
| | - Feipeng Zhu
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China.
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China.
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China.
- State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
| | - Changhe Wang
- Neuroscience Research Center, Institute of Mitochondrial Biology and Medicine, Key Laboratory of Biomedical Information Engineering of Ministry of Education, School of Life Science and Technology, Xi'an Jiaotong University, Xi'an, 710049, China.
- Department of Neurology, the First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China.
| | - Zhuan Zhou
- State Key Laboratory of Membrane Biology and Beijing Key Laboratory of Cardiometabolic Molecular Medicine, Institute of Molecular Medicine, College of Future Technology, Peking University, Beijing, 100871, China.
- Peking-Tsinghua Center for Life Sciences, Peking University, Beijing, 100871, China.
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing, 100871, China.
| |
Collapse
|
3
|
Park K, Clare K, Volkow ND, Pan Y, Du C. Cocaine's effects on the reactivity of the medial prefrontal cortex to ventral tegmental area stimulation: optical imaging study in mice. Addiction 2022; 117:2242-2253. [PMID: 35293056 PMCID: PMC9801493 DOI: 10.1111/add.15869] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Accepted: 02/18/2022] [Indexed: 01/03/2023]
Abstract
BACKGROUND AND AIMS The prefrontal cortex (PFC) is modulated by dopaminergic and glutamatergic neurons that project from the ventral tegmental area (VTA) and disruption of this modulation might facilitate impulsive behaviors during cocaine intoxication. Here, we assessed the effects of acute cocaine (30 mg/kg, i.p.) on the reactivity of the PFC to VTA stimulation. METHODS Using a genetically encoded calcium indicator (GCaMP6f), we optically imaged the neuronal Ca2+ reactance in medial PFC (mPFC) in response to 'tonic-like' (5 Hz) and 'phasic-like' (50 Hz) electrical VTA stimulation. The high temporal and spatial resolutions of our optical system allowed us to capture single Ca2+ neuronal transients from individual stimuli with 'tonic-like' stimulation and to visualize single neuronal activation evoked by 'phasic-like' VTA stimulation. RESULTS 'Tonic-like' VTA stimulation induced a rapid increase in mean neuronal Ca2+ in mPFC followed by a plateau and recovery upon termination of stimulation. After cocaine, the mPFC sensitivity to 'tonic-like' VTA stimulation was attenuated, with a 50.4% reduction (P = 0.03) in the number of Ca2+ transients corresponding to single electrical stimuli but the recovery time was lengthened (4.30 ± 0.25 sec to 5.41 ± 0.24 sec, P = 0.03). 'Phasic-like' stimulation evoked a rapid Ca2+ fluorescence increase in mPFC with an immediate decay process, and while cocaine did not affect the peak response (7.17 ± 1.07% versus 7.13 ± 0.96%, P = 0.98) it shortened the recovery time to baseline (3.27 ± 0.11 sec versus 2.38 ± 0.23 sec, P = 0.005). CONCLUSIONS Acute cocaine impairs reactivity of medial prefrontal cortex (mPFC) to ventral tegmental area stimulation, decreasing its sensitivity to 'tonic-like' stimulation and lengthening the recovery time to return to baseline while shortening it for phasic stimulation. These changes in mPFC might contribute to cocaine binging during intoxication.
Collapse
Affiliation(s)
- Kicheon Park
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
| | - Kevin Clare
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
| | | | - Yingtian Pan
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
| | - Congwu Du
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
| |
Collapse
|
4
|
Ca 2+ channel blockade reduces cocaine's vasoconstriction and neurotoxicity in the prefrontal cortex. Transl Psychiatry 2021; 11:459. [PMID: 34489397 PMCID: PMC8421405 DOI: 10.1038/s41398-021-01573-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 07/23/2021] [Accepted: 08/17/2021] [Indexed: 02/08/2023] Open
Abstract
Cocaine profoundly affects both cerebral blood vessels and neuronal activity in the brain. The vasoconstrictive effects of cocaine, concurrently with its effects on neuronal [Ca2+]i accumulation are likely to jeopardize neuronal tissue that in the prefrontal cortex (PFC) could contribute to impaired self-regulation and compulsive cocaine consumption. Here we used optical imaging to study the cerebrovascular and neuronal effects of acute cocaine (1 mg/kg i.v.) and to examine whether selective blockade of L-type Ca2+ channels by Nifedipine (NIF) (0.5 mg/kg i.v.) would alleviate cocaine's effects on hemodynamics (measured with cerebral blood volume, HbT), oxygenation (measured with oxygenated hemoglobin, HbO2) and neuronal [Ca2+]i, which were concomitantly measured in the PFC of naive rats. Our results show that in the PFC acute cocaine significantly reduced flow delivery (HbT), increased neuronal [Ca2+]i accumulation and profoundly reduced tissue oxygenation (HbO2) and these effects were significantly attenuated by NIF pretreatment. They also show that cocaine-induced vasoconstriction is distinct from its increase of neuronal [Ca2+]i accumulation though both of them contribute to hypoxemia and both effects were attenuated by NIF. These results provide evidence that blockade of voltage-gated L-type Ca2+ channels might be beneficial in preventing vasoconstriction and neurotoxic effects of cocaine and give support for further clinical investigations to determine their value in reducing cocaine's neurotoxicity in cocaine use disorders.
Collapse
|
5
|
Park K, Liyanage AC, Koretsky AP, Pan Y, Du C. Optical imaging of stimulation-evoked cortical activity using GCaMP6f and jRGECO1a. Quant Imaging Med Surg 2021; 11:998-1009. [PMID: 33654672 PMCID: PMC7829166 DOI: 10.21037/qims-20-921] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
BACKGROUND Genetically encoded calcium indicators (GECIs), especially the GCaMP-based green fluorescence GECIs have been widely used for in vivo detection of neuronal activity in rodents by measuring intracellular neuronal Ca2+ changes. More recently, jRGECO1a, a red shifted GECI, has been reported to detect neuronal Ca2+ activation. This opens the possibility of using dual-color GECIs for simultaneous interrogation of different cell populations. However, there has been no report to compare the functional difference between these two GECIs for in vivo imaging. Here, a comparative study is reported on neuronal responses to sensory stimulation using GCaMP6f and jRGECO1a that were virally delivered into the neurons in the somatosensory cortex of two different groups of animals, respectively. METHODS GCaMP6f and jRGECO1a GECI were virally delivered to sensory cortex. After 3-4 weeks, the animals were imaged to capture the spatiotemporal changes of neuronal Ca2+ and the hemodynamic responses to forepaw electrical stimulation (0.3 mA, 0.3 ms/pulse, 0.03 Hz). The stimulation-evoked neuronal Ca2+ transients expressed with GCaMP6f or jRGECO1a were recorded during the baseline period and after an acute cocaine administration (1 mg/kg, i.v.). RESULTS Histology confirmed that the efficiency of jRGECO1a and GCaMP6f expression into the cortical neurons was similar, i.e., 34%±3% and 32.7%±1.6%, respectively. Our imaging in vivo showed that the hemodynamic responses to the stimulation were the same between jRGECO1a and GCaMP6f expressed groups. Although the stimulation-evoked fluorescence change (∆F/F) and the time-to-peak of the neuronal Ca2+ transients were not significantly different between these two indicators, the full-width-half-maximum (FWHM) duration of the ∆F/F rise in the jRGECO1a-expressed group (0.16±0.02 s) was ~50 ms or 46% longer than that of the GCaMP6f group (0.11±0.003 s), indicating a longer recovery time in jRGECO1a than in GCaMP6f transients (P<0.01). This is likely due to the longer off rate of jRGECO1a than that of GCaMP6f. After cocaine, the time-to-peak of Ca2+ transients was delayed and their FWHM duration was prolonged for both expression groups, indicating that these are cocaine's effects on neuronal Ca2+ signaling and not artifacts due to the property differences of the GCEIs. CONCLUSIONS This study shows that both jRGECO1a and GCaMP6f have sufficient sensitivity for tracking single-stimulation-evoked Ca2+ transients to detect neuronal activities from the brain. Since these GECIs are emitted at the different wavelengths, it will be possible to use them together to characterize the activity of different cell types (e.g., neurons and astrocytes) to study brain activation and brain functional changes in normal or diseased brains.
Collapse
Affiliation(s)
- Kicheon Park
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
| | - Anuki C. Liyanage
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
| | - Alan P. Koretsky
- Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA
| | - Yingtian Pan
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
| | - Congwu Du
- Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY, USA
| |
Collapse
|
6
|
Shen G, Shi W. Amphetamine promotes cortical Up state: Role of adrenergic receptors. Addict Biol 2021; 26:e12879. [PMID: 32003119 DOI: 10.1111/adb.12879] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 12/10/2019] [Accepted: 01/10/2020] [Indexed: 11/30/2022]
Abstract
Cortical neurons oscillate synchronously between the Up and Down state during slow-wave sleep and general anesthesia. Using local-field-potential recording in the rat prefrontal cortex (PFC), we have shown that systemic administration of methylphenidate promotes PFC Up states and reduces PFC slow oscillation, suggesting a depolarizing effect of the drug on PFC neurons. Here, we report that systemic injection of d-amphetamine produced similar effects. Our evidence further suggests that norepinephrine (NE) plays a major role in the effects of d-amphetamine since they were mimicked by the NE reuptake inhibitors tomoxetine and nisoxetine and completely blocked by the α1 receptor antagonist prazosin. The effects of d-amphetamine persisted, however, in the presence of α2 or β receptor blockade. Experiments with α1 subtype-selective antagonists further suggest that d-amphetamine's effects depend on activation of central, but not peripheral, α1A receptors. Unexpectedly, the putative α1 receptor agonist cirazoline failed to mimic the effects of d-amphetamine. Previous studies suggest that cirazoline is also an antagonist at α2 receptors. Furthermore, it is a partial, not full, agonist at α1B and α1D receptors. Whether or not these properties of cirazoline contribute to its failure to mimic d-amphetamine's effects remains to be determined. Methylphenidate and d-amphetamine are two most common medications for attention-deficit/hyperactivity disorder (ADHD). Both, however, are associated with adverse effects including abuse potential and psychotomimetic effects. Further understanding of their mechanisms of action will help develop safer treatments for ADHD and offer new insights into drug addiction and psychosis.
Collapse
Affiliation(s)
- Guofang Shen
- Department of Pharmaceutical and Administrative Sciences Loma Linda University School of Pharmacy Loma Linda CA USA
| | - Wei‐Xing Shi
- Department of Pharmaceutical and Administrative Sciences Loma Linda University School of Pharmacy Loma Linda CA USA
- Department of Basic Sciences Loma Linda University School of Medicine Loma Linda CA USA
| |
Collapse
|
7
|
Conditional, inducible gene silencing in dopamine neurons reveals a sex-specific role for Rit2 GTPase in acute cocaine response and striatal function. Neuropsychopharmacology 2020; 45:384-393. [PMID: 31277075 PMCID: PMC6901441 DOI: 10.1038/s41386-019-0457-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 06/26/2019] [Accepted: 06/28/2019] [Indexed: 12/13/2022]
Abstract
Dopamine (DA) signaling is critical for movement, motivation, and addictive behavior. The neuronal GTPase, Rit2, is enriched in DA neurons (DANs), binds directly to the DA transporter (DAT), and is implicated in several DA-related neuropsychiatric disorders. However, it remains unknown whether Rit2 plays a role in either DAergic signaling and/or DA-dependent behaviors. Here we leveraged the TET-OFF system to conditionally silence Rit2 in Pitx3IRES2-tTA mouse DANs. Following DAergic Rit2 knockdown (Rit2-KD), mice displayed an anxiolytic phenotype, with no change in baseline locomotion. Further, males exhibited increased acute cocaine sensitivity, whereas DAergic Rit2-KD suppressed acute cocaine sensitivity in females. DAergic Rit2-KD did not affect presynaptic TH and DAT protein levels in females, nor was TH was affected in males; however, DAT was significantly diminished in males. Paradoxically, despite decreased DAT levels in males, striatal DA uptake was enhanced, but was not due to enhanced DAT surface expression in either dorsal or ventral striatum. Finally, patch recordings in nucleus accumbens (NAcc) medium spiny neurons (MSNs) revealed reciprocal changes in spontaneous EPSP (sEPSP) frequency in male and female D1+ and D2+ MSNs following DAergic Rit2-KD. In males, sEPSP frequency was decreased in D1+, but not D2+, MSNs, whereas in females sEPSP frequency decreased in D2+, but not D1+, MSNs. Moreover, DAergic Rit2-KD abolished the ability of cocaine to reduce sEPSP frequency in D1+, but not D2+, male MSNs. Taken together, our studies are among the first to acheive AAV-mediated, conditional and inducible DAergic knockdown in vivo. Importantly, our results provide the first evidence that DAergic Rit2 expression differentially impacts striatal function and DA-dependent behaviors in males and females.
Collapse
|
8
|
Trantham-Davidson H, Chandler LJ. Alcohol-induced alterations in dopamine modulation of prefrontal activity. Alcohol 2015; 49:773-9. [PMID: 26558348 DOI: 10.1016/j.alcohol.2015.09.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 09/01/2015] [Accepted: 09/01/2015] [Indexed: 02/06/2023]
Abstract
Long-term alcohol use leads to persistent cognitive deficits that may be associated with maladaptive changes in the neurocircuitry that mediates executive functions. Impairments caused by these changes can persist well into abstinence and have a negative impact on quality of life and job performance, and can increase the probability of relapse. Many of the changes that affect cognitive function appear to involve dysregulation of the mesocortical dopamine system. This includes changes in dopamine release and alterations in dopamine receptor expression and function in the medial prefrontal cortex (PFC). This review summarizes the cellular effects of acute and chronic ethanol exposure on dopamine release and dopamine receptor function in the PFC with the goal of providing greater understanding of the effects of alcohol-use disorders on the dopamine system and how this relates to deficits in the executive function of the PFC.
Collapse
Affiliation(s)
| | - L Judson Chandler
- Department of Neuroscience, Medical University of South Carolina, Charleston, SC 29425, USA
| |
Collapse
|
9
|
Beckley JT, Woodward JJ. Volatile solvents as drugs of abuse: focus on the cortico-mesolimbic circuitry. Neuropsychopharmacology 2013; 38:2555-67. [PMID: 23954847 PMCID: PMC3828545 DOI: 10.1038/npp.2013.206] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 08/12/2013] [Accepted: 08/13/2013] [Indexed: 12/15/2022]
Abstract
Volatile solvents such as those found in fuels, paints, and thinners are found throughout the world and are used in a variety of industrial applications. However, these compounds are also often intentionally inhaled at high concentrations to produce intoxication. While solvent use has been recognized as a potential drug problem for many years, research on the sites and mechanisms of action of these compounds lags behind that of other drugs of abuse. In this review, we first discuss the epidemiology of voluntary solvent use throughout the world and then consider what is known about their basic pharmacology and how this may explain their use as drugs of abuse. We next present data from preclinical and clinical studies indicating that these substances induce common addiction sequelae such as dependence, withdrawal, and cognitive impairments. We describe how toluene, the most commonly studied psychoactive volatile solvent, alters synaptic transmission in key brain circuits such as the mesolimbic dopamine system and medial prefrontal cortex (mPFC) that are thought to underlie addiction pathology. Finally, we make the case that activity in mPFC circuits is a critical regulator of the mesolimbic dopamine system's ability to respond to volatile solvents like toluene. Overall, this review provides evidence that volatile solvents have high abuse liability because of their selective effects on critical nodes of the addiction neurocircuitry, and underscores the need for more research into how these compounds induce adaptations in neural circuits that underlie addiction pathology.
Collapse
Affiliation(s)
- Jacob T Beckley
- Department of Neurosciences, Medical University of South Carolina, Charleston, SC, USA,Center for Drug and Alcohol Programs, Department of Psychiatry/Neurosciences, Medical University of South Carolina, Charleston, SC, USA
| | - John J Woodward
- Department of Neurosciences, Medical University of South Carolina, Charleston, SC, USA,Center for Drug and Alcohol Programs, Department of Psychiatry/Neurosciences, Medical University of South Carolina, Charleston, SC, USA,Department of Neurosciences, Medical University of South Carolina, IOP 4 North, 67 President Street, MSC 861, Charleston, SC 29425, USA, Tel: +(843) 792 5225, Fax: +(843) 792 7353, E-mail:
| |
Collapse
|
10
|
Medial prefrontal cortex inversely regulates toluene-induced changes in markers of synaptic plasticity of mesolimbic dopamine neurons. J Neurosci 2013; 33:804-13. [PMID: 23303956 DOI: 10.1523/jneurosci.3729-12.2013] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Toluene is a volatile solvent that is intentionally inhaled by children, adolescents, and adults for its intoxicating effects. Although voluntary use of toluene suggests that it possesses rewarding properties and abuse potential, it is unknown whether toluene alters excitatory synaptic transmission in reward-sensitive dopamine neurons like other drugs of abuse. Here, using a combination of retrograde labeling and slice electrophysiology, we show that a brief in vivo exposure of rats to a behaviorally relevant concentration of toluene vapor enhances glutamatergic synaptic strength of dopamine (DA) neurons projecting to nucleus accumbens core and medial shell neurons. This effect persisted for up to 3 d in mesoaccumbens core DA neurons and for at least 21 d in those projecting to the medial shell. In contrast, toluene vapor exposure had no effect on synaptic strength of DA neurons that project to the medial prefrontal cortex (mPFC). Furthermore, infusion of GABAergic modulators into the mPFC before vapor exposure to pharmacologically manipulate output, inhibited, or potentiated toluene's action on mesoaccumbens DA neurons. Together, the results of these studies indicate that toluene induces a target-selective increase in mesolimbic DA neuron synaptic transmission and strongly implicates the mPFC as an important regulator of drug-induced plasticity of mesolimbic dopamine neurons.
Collapse
|
11
|
Hearing MC, Zink AN, Wickman K. Cocaine-induced adaptations in metabotropic inhibitory signaling in the mesocorticolimbic system. Rev Neurosci 2012; 23:325-51. [PMID: 22944653 DOI: 10.1515/revneuro-2012-0045] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Accepted: 06/11/2012] [Indexed: 12/17/2022]
Abstract
The addictive properties of psychostimulants such as cocaine are rooted in their ability to activate the mesocorticolimbic dopamine (DA) system. This system consists primarily of dopaminergic projections arising from the ventral tegmental area (VTA) and projecting to the limbic and cortical brain regions, such as the nucleus accumbens (NAc) and prefrontal cortex (PFC). While the basic anatomy and functional relevance of the mesocorticolimbic DA system is relatively well-established, a key challenge remaining in addiction research is to understand where and how molecular adaptations and corresponding changes in function of this system facilitate a pathological desire to seek and take drugs. Several lines of evidence indicate that inhibitory signaling, particularly signaling mediated by the Gi/o class of heterotrimeric GTP-binding proteins (G proteins), plays a key role in the acute and persistent effects of drugs of abuse. Moreover, recent evidence argues that these signaling pathways are targets of drug-induced adaptations. In this review we discuss inhibitory signaling pathways involving DA and the inhibitory neurotransmitter GABA in two brain regions - the VTA and PFC - that are central to the effects of acute and repeated cocaine exposure and represent sites of adaptations linked to addiction-related behaviors including sensitization, craving, and relapse.
Collapse
Affiliation(s)
- Matthew C Hearing
- Department of Pharmacology, University of Minnesota, Minneapolis, MN, USA
| | | | | |
Collapse
|
12
|
Kroener S, Chandler LJ, Phillips PEM, Seamans JK. Dopamine modulates persistent synaptic activity and enhances the signal-to-noise ratio in the prefrontal cortex. PLoS One 2009; 4:e6507. [PMID: 19654866 PMCID: PMC2715878 DOI: 10.1371/journal.pone.0006507] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2009] [Accepted: 07/11/2009] [Indexed: 11/19/2022] Open
Abstract
Background The importance of dopamine (DA) for prefrontal cortical (PFC) cognitive functions is widely recognized, but its mechanisms of action remain controversial. DA is thought to increase signal gain in active networks according to an inverted U dose-response curve, and these effects may depend on both tonic and phasic release of DA from midbrain ventral tegmental area (VTA) neurons. Methodology/Principal Findings We used patch-clamp recordings in organotypic co-cultures of the PFC, hippocampus and VTA to study DA modulation of spontaneous network activity in the form of Up-states and signals in the form of synchronous EPSP trains. These cultures possessed a tonic DA level and stimulation of the VTA evoked DA transients within the PFC. The addition of high (≥1 µM) concentrations of exogenous DA to the cultures reduced Up-states and diminished excitatory synaptic inputs (EPSPs) evoked during the Down-state. Increasing endogenous DA via bath application of cocaine also reduced Up-states. Lower concentrations of exogenous DA (0.1 µM) had no effect on the up-state itself, but they selectively increased the efficiency of a train of EPSPs to evoke spikes during the Up-state. When the background DA was eliminated by depleting DA with reserpine and alpha-methyl-p-tyrosine, or by preparing corticolimbic co-cultures without the VTA slice, Up-states could be enhanced by low concentrations (0.1–1 µM) of DA that had no effect in the VTA containing cultures. Finally, in spite of the concentration-dependent effects on Up-states, exogenous DA at all but the lowest concentrations increased intracellular current-pulse evoked firing in all cultures underlining the complexity of DA's effects in an active network. Conclusions/Significance Taken together, these data show concentration-dependent effects of DA on global PFC network activity and they demonstrate a mechanism through which optimal levels of DA can modulate signal gain to support cognitive functioning.
Collapse
Affiliation(s)
- Sven Kroener
- Department of Neurosciences, Medical University of South Carolina, Charleston, South Carolina, United States of America.
| | | | | | | |
Collapse
|
13
|
Du C, Yu M, Volkow ND, Koretsky AP, Fowler JS, Benveniste H. Cocaine increases the intracellular calcium concentration in brain independently of its cerebrovascular effects. J Neurosci 2006; 26:11522-31. [PMID: 17093073 PMCID: PMC6674780 DOI: 10.1523/jneurosci.3612-06.2006] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Cocaine abuse increases the risk of life-threatening neurological complications such as strokes and seizures. Although the vasoconstricting properties of cocaine underlie its cerebrovascular effects, the mechanisms underlying its neurotoxicity remain incompletely understood. Here, we use optical techniques to measure cerebral blood volume, hemoglobin oxygenation (S(t)O(2)), and intracellular calcium ([Ca(2+)](i)) to test the hypothesis that cocaine increases [Ca(2+)](i) in the brain. The effects of cocaine were compared with those of methylphenidate, which has similar catecholaminergic effects as cocaine (except for serotonin increases) but no local anesthetic properties, and of lidocaine, which has similar local anesthetic effects as cocaine but is devoid of catecholaminergic actions. To control for the hemodynamic effects of cocaine, we assessed the effects of cocaine in animals in which normal blood pressure was maintained by infusion of phenylephrine, and we also measured the effects of transient hypotension (mimicking that induced by cocaine). We show that cocaine induced significant increases ( approximately 10-15%) in [Ca(2+)](i) that were independent of its hemodynamic effects and of the anesthetic used (isofluorance or alpha-chloralose). Lidocaine but not methylphenidate also induced significant [Ca(2+)](i) increases ( approximately 10-13%). This indicates that cocaine at a dose within the range used by drug users significantly increases the [Ca(2+)](i) in the brain and its local anesthetic, but neither its catecholaminergic nor its hemodynamic actions, underlies this effect. Cocaine-induced [Ca(2+)](i) increases are likely to accentuate the neurotoxic effects from cocaine-induced vasoconstriction and to facilitate the occurrence of seizures from the catecholaminergic effects of cocaine. These findings support the use of calcium channel blockers as a strategy to minimize the neurotoxic effects of cocaine.
Collapse
Affiliation(s)
- Congwu Du
- Medical Department and
- Department of Anesthesiology, State University of New York at Stony Brook, Stony Brook, New York 11794-8700
| | | | | | - Alan P. Koretsky
- Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892, and
| | - Joanna S. Fowler
- Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973-5000
| | - Helene Benveniste
- Medical Department and
- Department of Anesthesiology, State University of New York at Stony Brook, Stony Brook, New York 11794-8700
| |
Collapse
|
14
|
Wood SC, Fay J, Sage JR, Anagnostaras SG. Cocaine and Pavlovian fear conditioning: dose-effect analysis. Behav Brain Res 2006; 176:244-50. [PMID: 17098299 PMCID: PMC1822737 DOI: 10.1016/j.bbr.2006.10.008] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2006] [Revised: 10/05/2006] [Accepted: 10/07/2006] [Indexed: 11/22/2022]
Abstract
Emerging evidence suggests that cocaine and other drugs of abuse can interfere with many aspects of cognitive functioning. The authors examined the effects of 0.1-15mg/kg of cocaine on Pavlovian contextual and cued fear conditioning in mice. As expected, pre-training cocaine dose-dependently produced hyperactivity and disrupted freezing. Surprisingly, when the mice were tested off-drug later, the group pre-treated with a moderate dose of cocaine (15mg/kg) displayed significantly less contextual and cued memory, compared to saline control animals. Conversely, mice pre-treated with a very low dose of cocaine (0.1mg/kg) showed significantly enhanced fear memory for both context and tone, compared to controls. These results were not due to cocaine's anesthetic effects, as shock reactivity was unaffected by cocaine. The data suggest that despite cocaine's reputation as a performance-enhancing and anxiogenic drug, this effect is seen only at very low doses, whereas a moderate dose disrupts hippocampus and amygdala-dependent fear conditioning.
Collapse
Affiliation(s)
- Suzanne C Wood
- Department of Psychology, University of California, San Diego, 9500 Gilman Drive 0109, LaJolla, CA 92093-0109, United States.
| | | | | | | |
Collapse
|
15
|
Sun W, Rebec GV. Repeated cocaine self-administration alters processing of cocaine-related information in rat prefrontal cortex. J Neurosci 2006; 26:8004-8. [PMID: 16870745 PMCID: PMC6674208 DOI: 10.1523/jneurosci.1413-06.2006] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
One of the core symptoms of cocaine addiction is compulsive drug-seeking behavior. Although the precise neural substrates are unknown, it has been hypothesized that this behavior involves cocaine-induced hypofunction of the prefrontal cortex (PFC) or "hypofrontality." To test this hypothesis, PFC neuronal activity was monitored in rats during approximately 3 weeks of cocaine self-administration (SA). Rats were trained to press a lever to self-administer cocaine in daily 2 h sessions. Responding was reinforced contingent on a modified fixed-ratio 5 schedule of reinforcement. In the first SA session, the overall firing rate and burst rate were significantly decreased after cocaine infusions relative to the period immediately before the session. These effects disappeared after > or = 10 d of drug SA and were replaced by a significant increase in burst duration and firing rate within a burst. Notably, however, the level of basal activity before the first drug infusion of each SA session decreased significantly after multiple weeks of cocaine exposure. Collectively, these data support the view that although repeated sessions of cocaine SA decrease basal PFC activity, increased burst-related firing in response to cocaine infusions suggests that processing of cocaine-related information is enhanced and may contribute to increased control by cocaine over cocaine-seeking behavior.
Collapse
|
16
|
Dackis CA, O'brien CP. Clinical implications of cocaine-induced cortical depression. Neuropsychopharmacology 2005; 30:1033; author reply 1034-5. [PMID: 15841088 DOI: 10.1038/sj.npp.1300701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|