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1.
Neurobiol Dis ; 134: 104673, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31734455

RESUMO

The recently developed DJ-1 knockout (KO) rat models the DJ-1 (or PARK7) loss-of-function mutation responsible for one form of early-onset familial Parkinson's disease (PD). Prior studies demonstrate that DJ-1 KO rats present progressive dopamine (DA) cell body degeneration in the substantia nigra pars compacta between 4 and 8 months of age. Furthermore, as some motor deficits emerge before the significant loss of DA cells, this mutation may yield a period of DA neuron dysfunction preceding cell death that may also contribute to cognitive impairments in early PD. However, cognitive functions subserved by corticostriatal circuitry, as well as additional alterations to the neurochemistry of monoamine systems, are largely uncharacterized in the DJ-1 KO rat. We therefore assessed a variety of striatally-mediated behavioral tasks, as well as the integrity of dopamine and serotonin systems, in male DJ-1 KO rats and wild-type (WT) controls at 4, 6, and 8 months of age. We demonstrate that DJ-1 KO rats exhibited motor impairments, but have intact goal-directed control over behavior in an appetitive instrumental learning task. Further, preprotachykinin mRNA expression, a post-synaptic indicator of DA signaling, was significantly decreased in 4-month DJ-1 KO rats, while DA transporter binding in the dorsal striatum did not differ between genotypes at any of the ages examined. Striatal tyrosine hydroxylase levels were significantly increased in 8-month DJ-1 KO rats and tended to be higher than WT at 4 and 6 months. Lastly, serotonin transporter binding was increased in the medial and orbitofrontal cortices of 4-month old DJ-1 KO rats. These results suggest that the nigrostriatal dopaminergic and prefrontal serotoninergic systems are altered early in the progression of DJ-1 KO pathology, despite no overt loss of the DA innervation of the striatum, and thus may be associated with early alterations in the functions of corticostriatal systems.


Assuntos
Comportamento Animal/fisiologia , Corpo Estriado/fisiologia , Doença de Parkinson/fisiopatologia , Proteína Desglicase DJ-1/fisiologia , Animais , Condicionamento Operante/fisiologia , Modelos Animais de Doenças , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Técnicas de Inativação de Genes , Masculino , Doença de Parkinson/psicologia , Córtex Pré-Frontal/metabolismo , Proteína Desglicase DJ-1/genética , Precursores de Proteínas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Ratos Long-Evans , Taquicininas/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
2.
Community Ment Health J ; 56(5): 947-958, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32006294

RESUMO

Despite the existence of numerous efficacious treatments for mental disorders, many individuals in need do not receive adequate treatment particularly racial and ethnic minorities. Community stakeholders can provide: (1) a more nuanced understanding of community mental health needs, and in (2) informing the planning and provision of mental health services. Qualitative data for this mental health needs assessment come from 61 individuals who represent local residents and/or consumers of mental health services, Executive Directors, providers of mental health and non-mental health community based services. We identified systems-related and psychosocial barriers to seeking mental health services: difficulty navigating the mental health system, language barriers, dearth of culturally competent providers; and mental health stigma and mental health literacy and non-Western notions of mental health. Collaborative efforts across stakeholders are called for to address the mental health needs of racial and ethnic minorities in a local community.


Assuntos
Serviços de Saúde Mental , Etnicidade , Humanos , Grupos Minoritários , Avaliação das Necessidades , New England
3.
J Clin Psychol ; 76(1): 195-209, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31583715

RESUMO

OBJECTIVE(S): This qualitative study aimed to elucidate barriers and facilitators faced by individuals with serious mental illness in establishing positive therapeutic relationships within the public sector. METHOD: Twenty-two individuals, receiving inpatient treatment and near discharge from three state psychiatric facilities, participated. The sample was diverse with respect to gender (60 % male) and race/ethnicity, with a mean age of 40 years (standard deviation = 12.91). Thematic analysis and a contextualist lens were used to analyze the data. RESULTS: Results indicated that inadequate meeting time, lack of clinically relevant communication, and discrepancies in client/provider perspectives, impeded positive therapeutic relationships. Facilitators to therapeutic relationships included feelings heard and understood by providers, comprehensive, timely discharge plans, and thinking broadly about aftercare. CONCLUSIONS: Cultivating positive therapeutic relationships is especially difficult in resource-challenged settings. Enhanced client-provider communication and individually tailored aftercare planning can enhance inpatient therapeutic relationships, convey a greater sense of understanding of clients, and facilitate client-provider collaboration.


Assuntos
Hospitais Psiquiátricos , Hospitais Estaduais , Transtornos Mentais/terapia , Satisfação do Paciente , Relações Profissional-Paciente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa
4.
J Physiol ; 595(4): 1393-1412, 2017 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-27682823

RESUMO

KEY POINTS: The lateral habenula (LHb) has been implicated in regulation of drug-seeking behaviours through aversion-mediated learning. In this study, we recorded neuronal activity in the LHb of rats during an operant task before and after ethanol-induced conditioned taste aversion (CTA) to saccharin. Ethanol-induced CTA caused significantly higher baseline firing rates in LHb neurons, as well as elevated firing rates in response to cue presentation, lever press and saccharin taste. In a separate cohort of rats, we found that bilateral LHb lesions blocked ethanol-induced CTA. Our results strongly suggest that excitation of LHb neurons is required for ethanol-induced CTA, and point towards a mechanism through which LHb firing may regulate voluntary ethanol consumption. ABSTRACT: Ethanol, like other drugs of abuse, has both rewarding and aversive properties. Previous work suggests that sensitivity to ethanol's aversive effects negatively modulates voluntary alcohol intake and thus may be important in vulnerability to developing alcohol use disorders. We previously found that rats with lesions of the lateral habenula (LHb), which is implicated in aversion-mediated learning, show accelerated escalation of voluntary ethanol consumption. To understand neural encoding in the LHb contributing to ethanol-induced aversion, we recorded neural firing in the LHb of freely behaving, water-deprived rats before and after an ethanol-induced (1.5 g kg-1 20% ethanol, i.p.) conditioned taste aversion (CTA) to saccharin taste. Ethanol-induced CTA strongly decreased motivation for saccharin in an operant task to obtain the tastant. Comparison of LHb neural firing before and after CTA induction revealed four main differences in firing properties. First, baseline firing after CTA induction was significantly higher. Second, firing evoked by cues signalling saccharin availability shifted from a pattern of primarily inhibition before CTA to primarily excitation after CTA induction. Third, CTA induction reduced the magnitude of lever press-evoked inhibition. Finally, firing rates were significantly higher during consumption of the devalued saccharin solution after CTA induction. Next, we studied sham- and LHb-lesioned rats in our operant CTA paradigm and found that LHb lesion significantly attenuated CTA effects in the operant task. Our data demonstrate the importance of LHb excitation in regulating expression of ethanol-induced aversion and suggest a mechanism for its role in modulating escalation of voluntary ethanol intake.


Assuntos
Consumo de Bebidas Alcoólicas/fisiopatologia , Etanol/toxicidade , Potenciais Somatossensoriais Evocados , Habenula/fisiologia , Neurônios/fisiologia , Distúrbios do Paladar/fisiopatologia , Percepção Gustatória , Animais , Condicionamento Operante , Habenula/citologia , Masculino , Ratos , Ratos Long-Evans , Distúrbios do Paladar/etiologia
5.
Eur J Neurosci ; 45(11): 1418-1430, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28394447

RESUMO

Opioid signaling in the nucleus accumbens shell (sNAcc) has been implicated in hedonic feeding and binge eating behavior. The sNAcc projects to the lateral hypothalamus (LH), and this pathway has been suggested to modulate palatability-driven feeding behavior. In this study, we investigated the effects of sNAcc mu opioid receptor (MOR) stimulation on firing rates of LH neurons in previously sated rats. Neural firing in the LH was recorded while food-deprived rats performed an operant task to obtain sweetened Intralipid (a 4% fat emulsion containing 5% sucrose) before and after bilateral sNAcc infusion of either a MOR agonist [D-Ala2, N-MePhe4, Gly-ol]-enkephalin (DAMGO) or a saline control solution. During sessions in which saline was infused into the sNAcc, the number of trials completed after infusion were significantly lower than the number completed before infusion, likely reflecting animals' increased satiety state. During sessions in which DAMGO was infused into the sNAcc, the decrease in the number of trials completed (comparing post- vs. pre-infusion trials) was significantly attenuated. Electrophysiological recording showed that the percentage of LH neurons showing an excitatory response due to behavioral events (cue presentation, lever press, lever retraction, and consumption) was reduced in post vs. pre-saline infusion period. However, the percentage of LH neurons showing excitatory responses to the same behavioral events was similar in pre- and post-DAMGO infusion periods. These findings suggest that MOR stimulation in sNAcc leads to an increase in stimulus-evoked excitatory signaling in LH neurons which could contribute to preventing satiety-induced decline in palatable food intake.


Assuntos
Comportamento Alimentar , Hipotálamo/metabolismo , Neurônios/fisiologia , Núcleo Accumbens/metabolismo , Receptores Opioides mu/metabolismo , Saciação , Animais , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Potenciais Evocados , Hipotálamo/citologia , Hipotálamo/fisiologia , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurotransmissores/farmacologia , Núcleo Accumbens/citologia , Núcleo Accumbens/fisiologia , Ratos , Ratos Long-Evans , Receptores Opioides mu/agonistas
6.
Hippocampus ; 26(7): 892-8, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26815290

RESUMO

The goal of the present research was to assess the degree to which a pattern completion process operates in cue-induced relapse to cocaine-seeking behavior. Using a novel cue-preference version of the place preference task, rats were administered cocaine or saline, which resulted in a preference for the cocaine-paired cues. After 21 days of abstinence and prior to the preference test, for one group, PBS or naloxone was injected into the CA3 subregion of the hippocampus and for a second group, saline or naloxone was injected systemically. The results indicated that infusions of naloxone into CA3 or systemic injections produced a marked disruption for one and two cues, but had minimal disruptive effect for three or four cues, suggesting that naloxone injections disrupt CA3 function and trigger a deficit in a pattern completion process. Thus, it appears that cue-based activation of the dorsal CA3 might be a critical trigger via a pattern completion process. Based on additional analyses it appears that there is a disruption primarily for object touches for one cue naloxone injections into the CA3 or systemic injections, but no effect on time (spatial context). © 2016 Wiley Periodicals, Inc.


Assuntos
Região CA3 Hipocampal/efeitos dos fármacos , Fármacos do Sistema Nervoso Central/farmacologia , Transtornos Relacionados ao Uso de Cocaína/tratamento farmacológico , Comportamento de Procura de Droga/efeitos dos fármacos , Naloxona/farmacologia , Animais , Região CA3 Hipocampal/patologia , Região CA3 Hipocampal/fisiopatologia , Cocaína/farmacologia , Transtornos Relacionados ao Uso de Cocaína/fisiopatologia , Condicionamento Operante , Sinais (Psicologia) , Modelos Animais de Doenças , Inibidores da Captação de Dopamina/farmacologia , Comportamento de Procura de Droga/fisiologia , Masculino , Ratos Long-Evans , Recidiva , Comportamento Espacial
7.
Synapse ; 70(4): 139-46, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26799527

RESUMO

Preclinical studies demonstrate that repeated, high-dose methamphetamine administrations rapidly decrease plasmalemmal dopamine uptake, which may contribute to aberrant dopamine accumulation, reactive species generation, and long-term dopaminergic deficits. The present study extends these findings by demonstrating a heretofore unreported, epitope-specific modification in the dopamine transporter caused by a methamphetamine regimen that induces these deficits. Specifically, repeated, high-dose methamphetamine injections (4 × 10 mg/kg/injection, 2-h intervals) rapidly decreased immunohistochemical detection of striatal dopamine transporter as assessed 1 h after the final methamphetamine exposure. In contrast, neither a single high dose (1 × 10 mg/kg) nor repeated injections of a lower dose (4 × 2 mg/kg/injection) induced this change. The high-dose regimen-induced alteration was only detected using antibodies directed against the N-terminus. Immunohistochemical staining using antibodies directed against the C-terminus did not reveal any changes. The high-dose regimen also did not alter dopamine transporter expression as assessed using [(125) I]RTI-55 autoradiography. These data suggest that the repeated, high-dose methamphetamine regimen alters the N-terminus of the dopamine transporter. Further, these data may be predictive of persistent dopamine deficits caused by the stimulant. Future studies of the signaling cascades involved should provide novel insight into potential mechanisms underlying the physiological and pathophysiological regulation of the dopamine transporter.


Assuntos
Dopaminérgicos/farmacologia , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Metanfetamina/farmacologia , Sequência de Aminoácidos , Animais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Dopaminérgicos/administração & dosagem , Dopaminérgicos/toxicidade , Proteínas da Membrana Plasmática de Transporte de Dopamina/química , Epitopos/metabolismo , Masculino , Metanfetamina/administração & dosagem , Metanfetamina/toxicidade , Dados de Sequência Molecular , Ligação Proteica , Domínios Proteicos , Ratos , Ratos Sprague-Dawley
8.
Med Care ; 52(11): 989-97, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25310525

RESUMO

BACKGROUND: Persistent disparities in access and quality of mental health care for Latinos indicate a need for evidence-based, culturally adapted, and outside-the-clinic-walls treatments. OBJECTIVE: Evaluate treatment effectiveness of telephone (ECLA-T) or face-to-face (ECLA-F) delivery of a 6-8 session cognitive behavioral therapy and care management intervention for low-income Latinos, as compared to usual care for depression. DESIGN: Multisite randomized controlled trial. SETTING: Eight community health clinics in Boston, Massachusetts and San Juan, Puerto Rico. PARTICIPANTS: 257 Latino patients recruited from primary care between May 2011 and September 2012. MAIN OUTCOME MEASURES: The primary outcome was severity of depression, assessed with the Patient Health Questionnaire-9 and the Hopkins Symptom Checklist-20. The secondary outcome was functioning over the previous 30 days, measured using the World Health Organization Disability Assessment Schedule (WHO-DAS 2.0). RESULTS: Both telephone and face-to-face versions of the Engagement and Counseling for Latinos (ECLA) were more effective than usual care. The effect sizes of both intervention conditions on Patient Health Questionnaire-9 were moderate when combined data from both sites are analyzed (0.56 and 0.64 for face-to-face and telephone, respectively). Similarly, effect sizes of ECLA-F and ECLA-T on the Hopkins Symptom Checklist were quite large in the Boston site (0.64 and 0.73. respectively) but not in Puerto Rico (0.10 and 0.03). CONCLUSIONS AND RELEVANCE: The intervention appears to help Latino patients reduce depressive symptoms and improve functioning. Of particular importance is the higher treatment initiation for the telephone versus face-to-face intervention (89.7% vs. 78.8%), which suggests that telephone-based care may improve access and quality of care.


Assuntos
Administração de Caso , Terapia Cognitivo-Comportamental/métodos , Transtorno Depressivo Maior/terapia , Hispânico ou Latino/psicologia , Pobreza/psicologia , Adolescente , Adulto , Idoso , Competência Cultural , Transtorno Depressivo Maior/etnologia , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Resultado do Tratamento , Adulto Jovem
9.
J Neurochem ; 125(4): 566-74, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23414433

RESUMO

Neurotoxic regimens of methamphetamine (METH) result in reactive microglia and astrocytes in striatum. Prior data indicate that rats with partial dopamine (DA) loss resulting from prior exposure to METH are resistant to further decreases in striatal DA when re-exposed to METH 30 days later. Such resistant animals also do not show an activated microglia phenotype, suggesting a relation between microglial activation and METH-induced neurotoxicity. To date, the astrocyte response in such resistance has not been examined. Thus, this study examined glial-fibrillary acidic protein (GFAP) and CD11b protein expression in striata of animals administered saline or a neurotoxic regimen of METH on post-natal days 60 and/or 90 (Saline:Saline, Saline:METH, METH:Saline, METH:METH). Consistent with previous work, animals experiencing acute toxicity (Saline:METH) showed both activated microglia and astocytes, whereas those resistant to the acute toxicity (METH:METH) did not show activated microglia. Interestingly, GFAP expression remained elevated in rats exposed to METH at PND60 (METH:Saline), and was not elevated further in resistant rats treated for the second time with METH (METH:METH). These data suggest that astrocytes remain reactive up to 30 days post-METH exposure. In addition, these data indicate that astrocyte reactivity does not reflect acute, METH-induced DA terminal toxicity, whereas microglial reactivity does.


Assuntos
Astrócitos/fisiologia , Dopamina/fisiologia , Metanfetamina/toxicidade , Microglia/fisiologia , Síndromes Neurotóxicas/fisiopatologia , Transtornos Relacionados ao Uso de Anfetaminas/genética , Transtornos Relacionados ao Uso de Anfetaminas/fisiopatologia , Animais , Astrócitos/efeitos dos fármacos , Antígeno CD11b/genética , Estimulantes do Sistema Nervoso Central/toxicidade , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/fisiopatologia , Febre/fisiopatologia , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/fisiologia , Proteína Glial Fibrilar Ácida/genética , Masculino , Microglia/efeitos dos fármacos , Síndromes Neurotóxicas/genética , Ratos , Ratos Sprague-Dawley
10.
J Neurochem ; 125(4): 555-65, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23480199

RESUMO

Methamphetamine-induced partial dopamine depletions are associated with impaired basal ganglia function, including decreased preprotachykinin mRNA expression and impaired transcriptional activation of activity-regulated, cytoskeleton-associated (Arc) gene in striatum. Recent work implicates deficits in phasic dopamine signaling as a potential mechanism linking methamphetamine-induced dopamine loss to impaired basal ganglia function. This study thus sought to establish a causal link between phasic dopamine transmission and altered basal ganglia function by determining whether the deficits in striatal neuron gene expression could be restored by increasing phasic dopamine release. Three weeks after pretreatment with saline or a neurotoxic regimen of methamphetamine, rats underwent phasic- or tonic-like stimulation of ascending dopamine neurons. Striatal gene expression was examined using in situ hybridization histochemistry. Phasic-like, but not tonic-like, stimulation induced immediate-early genes Arc and zif268 in both groups, despite the partial striatal dopamine denervation in methamphetamine-pretreated rats, with the Arc expression occurring in presumed striatonigral efferent neurons. Phasic-like stimulation also restored preprotachykinin mRNA expression. These results suggest that disruption of phasic dopamine signaling likely underlies methamphetamine-induced impairments in basal ganglia function, and that restoring phasic dopamine signaling may be a viable approach to manage long-term consequences of methamphetamine-induced dopamine loss on basal ganglia functions.


Assuntos
Corpo Estriado/fisiologia , Dopamina/fisiologia , Neurônios Dopaminérgicos/fisiologia , Feixe Prosencefálico Mediano/fisiologia , Metanfetamina/toxicidade , Síndromes Neurotóxicas/fisiopatologia , Transtornos Relacionados ao Uso de Anfetaminas/genética , Transtornos Relacionados ao Uso de Anfetaminas/fisiopatologia , Animais , Estimulantes do Sistema Nervoso Central/toxicidade , Corpo Estriado/efeitos dos fármacos , Proteínas do Citoesqueleto/genética , Denervação/métodos , Neurônios Dopaminérgicos/efeitos dos fármacos , Proteína 1 de Resposta de Crescimento Precoce/genética , Estimulação Elétrica/métodos , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/fisiologia , Genes Precoces/genética , Masculino , Feixe Prosencefálico Mediano/efeitos dos fármacos , Proteínas do Tecido Nervoso/genética , Síndromes Neurotóxicas/genética , Precursores de Proteínas/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Taquicininas/genética
11.
Eur J Neurosci ; 38(1): 2078-88, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23574406

RESUMO

Methamphetamine (METH) is a highly addictive drug that is also neurotoxic to central dopamine (DA) systems. Although striatal DA depletions induced by METH are associated with behavioral and cognitive impairments, the link between these phenomena remains poorly understood. Previous work in both METH-pretreated animals and the 6-hydroxydopamine model of Parkinson's disease suggests that a disruption of phasic DA signaling, which is important for learning and goal-directed behavior, may be such a link. However, previous studies used electrical stimulation to elicit phasic-like DA responses and were also performed under anesthesia, which alters DA neuron activity and presynaptic function. Here we investigated the consequences of METH-induced DA terminal loss on both electrically evoked phasic-like DA signals and so-called 'spontaneous' phasic DA transients measured by voltammetry in awake rats. Not ostensibly attributable to discrete stimuli, these subsecond DA changes may play a role in enhancing reward-cue associations. METH pretreatment reduced tissue DA content in the dorsomedial striatum and nucleus accumbens by ~55%. Analysis of phasic-like DA responses elicited by reinforcing stimulation revealed that METH pretreatment decreased their amplitude and underlying mechanisms for release and uptake to a similar degree as DA content in both striatal subregions. Most importantly, characteristics of DA transients were altered by METH-induced DA terminal loss, with amplitude and frequency decreased and duration increased. These results demonstrate for the first time that denervation of DA neurons alters naturally occurring DA transients and are consistent with diminished phasic DA signaling as a plausible mechanism linking METH-induced striatal DA depletions and cognitive deficits.


Assuntos
Dopaminérgicos/toxicidade , Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Metanfetamina/toxicidade , Transmissão Sináptica , Animais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Corpo Estriado/fisiologia , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/fisiologia , Masculino , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/metabolismo , Núcleo Accumbens/fisiologia , Ratos , Ratos Sprague-Dawley
12.
J Pharmacol Exp Ther ; 344(2): 511-21, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23230214

RESUMO

Nitric oxide is implicated in methamphetamine (METH)-induced neurotoxicity; however, the source of the nitric oxide has not been identified. Previous work has also revealed that animals with partial dopamine loss induced by a neurotoxic regimen of methamphetamine fail to exhibit further decreases in striatal dopamine when re-exposed to methamphetamine 7-30 days later. The current study examined nitric oxide synthase expression and activity and protein nitration in striata of animals administered saline or neurotoxic regimens of methamphetamine at postnatal days 60 and/or 90, resulting in four treatment groups: Saline:Saline, METH:Saline, Saline:METH, and METH:METH. Acute administration of methamphetamine on postnatal day 90 (Saline:METH and METH:METH) increased nitric oxide production, as evidenced by increased protein nitration. Methamphetamine did not, however, change the expression of endothelial or inducible isoforms of nitric oxide synthase, nor did it change the number of cells positive for neuronal nitric oxide synthase mRNA expression or the amount of neuronal nitric oxide synthase mRNA per cell. However, nitric oxide synthase activity in striatal interneurons was increased in the Saline:METH and METH:METH animals. These data suggest that increased nitric oxide production after a neurotoxic regimen of methamphetamine results from increased nitric oxide synthase activity, rather than an induction of mRNA, and that constitutively expressed neuronal nitric oxide synthase is the most likely source of nitric oxide after methamphetamine administration. Of interest, animals rendered resistant to further methamphetamine-induced dopamine depletions still show equivalent degrees of methamphetamine-induced nitric oxide production, suggesting that nitric oxide production alone in response to methamphetamine is not sufficient to induce acute neurotoxic injury.


Assuntos
Corpo Estriado/efeitos dos fármacos , Metanfetamina/toxicidade , Síndromes Neurotóxicas/enzimologia , Óxido Nítrico Sintase , Óxido Nítrico/biossíntese , Animais , Corpo Estriado/enzimologia , Corpo Estriado/metabolismo , Dopamina/metabolismo , Indução Enzimática , Hibridização In Situ , Interneurônios/efeitos dos fármacos , Interneurônios/enzimologia , Interneurônios/metabolismo , Isoenzimas , Masculino , Síndromes Neurotóxicas/etiologia , Síndromes Neurotóxicas/metabolismo , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo I/biossíntese , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico Sintase Tipo II/biossíntese , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/biossíntese , Óxido Nítrico Sintase Tipo III/metabolismo , Ratos , Ratos Sprague-Dawley
13.
Front Mol Neurosci ; 16: 1160157, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37251646

RESUMO

The shift from drug abuse to addiction is considered to arise from the transition between goal-directed and habitual control over drug behavior. Habitual responding for appetitive and skill-based behaviors is mediated by potentiated glutamate signaling in the dorsolateral striatum (DLS), but the state of the DLS glutamate system in the context of habitual drug-behavior remains undefined. Evidence from the nucleus accumbens of cocaine-experienced rats suggests that decreased transporter-mediated glutamate clearance and enhanced synaptic glutamate release contribute to the potentiated glutamate signaling that underlies the enduring vulnerability to relapse. Preliminary evidence from the dorsal striatum of cocaine-experienced rats suggests that this region exhibits similar alterations to glutamate clearance and release, but it is not known whether these glutamate dynamics are associated with goal-directed or habitual control over cocaine-seeking behavior. Therefore, we trained rats to self-administer cocaine in a chained cocaine-seeking and -taking paradigm, which yielded goal-directed, intermediate, and habitual cocaine-seeking rats. We then assessed glutamate clearance and release dynamics in the DLS of these rats using two different methods: synaptic transporter current (STC) recordings of patch-clamped astrocytes and the intensity-based glutamate sensing fluorescent reporter (iGluSnFr). While we observed a decreased rate of glutamate clearance in STCs evoked with single-pulse stimulation in cocaine-experienced rats, we did not observe any cocaine-induced differences in glutamate clearance rates from STCs evoked with high frequency stimulation (HFS) or iGluSnFr responses evoked with either double-pulse stimulation or HFS. Furthermore, GLT-1 protein expression in the DLS was unchanged in cocaine-experienced rats, regardless of their mode of control over cocaine-seeking behavior. Lastly, there were no differences in metrics of glutamate release between cocaine-experienced rats and yoked-saline controls in either assay. Together, these results suggest that glutamate clearance and release dynamics in the DLS are largely unaltered by a history of cocaine self-administration on this established cocaine seeking-taking paradigm, regardless of whether the control over the cocaine seeking behavior was habitual or goal directed.

14.
J Neurochem ; 123(5): 845-55, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22978492

RESUMO

The immediate-early gene Arc (activity-regulated cytoskeleton-associated protein) is provocative in the context of neuroplasticity because of its experience-dependent regulation and mRNA transport to and translation at activated synapses. Normal rats have more preproenkephalin-negative (ppe-neg; presumed striatonigral) neurons with cytoplasmic Arc mRNA than ppe-positive (ppe-pos; striatopallidal) neurons, despite equivalent numbers of these neurons showing novelty-induced transcriptional activation of Arc. Furthermore, rats with partial monoamine loss induced by methamphetamine (METH) show impaired Arc mRNA expression in both ppe-neg and ppe-pos neurons relative to normal animals following response-reversal learning. In this study, Arc expression induced by exposure to a novel environment was used to assess transcriptional activation and cytoplasmic localization of Arc mRNA in striatal efferent neuron subpopulations subsequent to METH-induced neurotoxicity. Partial monoamine depletion significantly altered Arc expression. Specifically, basal Arc expression was elevated, but novelty-induced transcriptional activation was abolished. Without novelty-induced Arc transcription, METH-pre-treated rats also had fewer neurons with cytoplasmic Arc mRNA expression, with the effect being greater for ppe-neg neurons. Thus, METH-induced neurotoxicity substantially alters striatal efferent neuron function at the level of Arc transcription, suggesting a long-term shift in basal ganglia neuroplasticity processes subsequent to METH-induced neurotoxicity. Such changes potentially underlie striatally based learning deficits associated with METH-induced neurotoxicity.


Assuntos
Estimulantes do Sistema Nervoso Central/toxicidade , Proteínas do Citoesqueleto/biossíntese , Dopamina/metabolismo , Metanfetamina/toxicidade , Proteínas do Tecido Nervoso/biossíntese , Neurônios Eferentes/metabolismo , Animais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Regulação da Expressão Gênica , Hibridização in Situ Fluorescente , Masculino , Neurônios Eferentes/efeitos dos fármacos , Síndromes Neurotóxicas/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Transcrição Gênica/efeitos dos fármacos
15.
Psychopharmacology (Berl) ; 239(1): 93-104, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34985532

RESUMO

RATIONALE: Methamphetamine (METH) exposure is associated with damage to central monoamine systems, particularly dopamine signaling. Rodent models of such damage have revealed a decrease in the amplitude of phasic dopamine signals and significant striatal dysfunction, including changes in the molecular, system, and behavioral functions of the striatum. Dopamine signaling through D1 receptors promotes corticostriatal long-term potentiation (LTP), a critical substrate of these striatal functions. OBJECTIVES: Therefore, the purpose of this study was to determine if METH-induced dopamine neurotoxicity would impair D1 receptor-dependent striatal LTP in mice. METHODS: Mice were treated with a METH binge regimen (4 × 10 mg/kg d,l-methamphetamine, s.c.) that recapitulates all of the known METH-induced neurotoxic effects observed in humans, including dopamine toxicity. Three weeks later, acute brain slices containing either the dorsomedial striatum (DMS) or dorsolateral striatum (DLS) were prepared, and plasticity was assessed using white matter, high-frequency stimulation (HFS), and striatal extracellular electrophysiology. RESULTS: Under these conditions, LTP was induced in brain slices containing the DMS from saline-pretreated mice, but not mice with METH-induced neurotoxicity. Furthermore, the LTP observed in DMS slices from saline-pretreated mice was blocked by the dopamine D1 receptor antagonist SCH23390, indicating that this LTP is dopamine D1 receptor-dependent. Finally, acute in vivo treatment of METH-pretreated mice with bupropion (50 mg/kg, i.p.) promoted LTP in DMS slices. CONCLUSIONS: Together, these studies demonstrate that METH-induced neurotoxicity impairs dopamine D1 receptor-dependent LTP within the DMS and that the FDA-approved drug bupropion restores induction of striatal LTP in mice with METH-induced dopamine neurotoxicity.


Assuntos
Metanfetamina , Síndromes Neurotóxicas , Animais , Corpo Estriado , Dopamina , Potenciação de Longa Duração , Metanfetamina/toxicidade , Camundongos
16.
J Neurochem ; 118(4): 668-76, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21668447

RESUMO

Neurotoxic doses of methamphetamine (METH) are known to cause depletions in striatal dopamine (DA) tissue content. However, the effects of METH-induced insults on dopaminergic neurotransmission are not fully understood. Here, we employed fast-scan cyclic voltammetry at a carbon-fiber microelectrode in the anesthetized rat striatum to assess the effects of a neurotoxic regimen of METH on phasic and tonic modes of dopaminergic signaling and underlying mechanisms of DA release and uptake. Extracellular DA was electrically evoked by stimulation of the medial forebrain bundle mimicking tonic and phasic firing patterns for dopaminergic cells and was monitored simultaneously in both the dorsomedial and dorsolateral striatum. Kinetic analysis of evoked recordings determined parameters describing DA release and uptake. Striatal DA tissue content was quantified by high performance liquid chromatography with electrochemical detection. METH-pretreatment (four doses of 7.5 or 10.0 mg/kg s.c.) induced DA depletions of ∼ 40% on average, which are reported in both striatal subregions. METH pre-treatment significantly decreased the amplitude of signals evoked by phasic, but not tonic, stimulation. Parameters for DA release and uptake were also similarly reduced by ∼ 40%, consistent with effects on evoked phasic-like responses and DA tissue content. Taken together, these results suggest that METH-pretreatment selectively diminishes phasic, but not tonic, dopaminergic signaling in the dorsal striatum.


Assuntos
Estimulantes do Sistema Nervoso Central/toxicidade , Corpo Estriado/fisiopatologia , Dopamina/fisiologia , Metanfetamina/toxicidade , Síndromes Neurotóxicas/fisiopatologia , Transdução de Sinais/fisiologia , Algoritmos , Animais , Dopamina/metabolismo , Estimulação Elétrica , Fenômenos Eletrofisiológicos , Espaço Extracelular/metabolismo , Cinética , Masculino , Microeletrodos , Neurônios/fisiologia , Oxidopamina , Doença de Parkinson Secundária/fisiopatologia , Ratos , Ratos Sprague-Dawley , Simpatectomia Química , Simpatolíticos
17.
J Clin Invest ; 131(10)2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-33848264

RESUMO

Opioid use disorder (OUD) has become a leading cause of death in the United States, yet current therapeutic strategies remain highly inadequate. To identify potential treatments for OUD, we screened a targeted selection of over 100 drugs using a recently developed opioid self-administration assay in zebrafish. This paradigm showed that finasteride, a steroidogenesis inhibitor approved for the treatment of benign prostatic hyperplasia and androgenetic alopecia, reduced self-administration of multiple opioids without affecting locomotion or feeding behavior. These findings were confirmed in rats; furthermore, finasteride reduced the physical signs associated with opioid withdrawal. In rat models of neuropathic pain, finasteride did not alter the antinociceptive effect of opioids and reduced withdrawal-induced hyperalgesia. Steroidomic analyses of the brains of fish treated with finasteride revealed a significant increase in dehydroepiandrosterone sulfate (DHEAS). Treatment with precursors of DHEAS reduced opioid self-administration in zebrafish in a fashion akin to the effects of finasteride. These results highlight the importance of steroidogenic pathways as a rich source of therapeutic targets for OUD and point to the potential of finasteride as a new treatment option for this disorder.


Assuntos
Inibidores de 5-alfa Redutase/farmacologia , Finasterida/farmacologia , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Animais , Modelos Animais de Doenças , Humanos , Masculino , Transtornos Relacionados ao Uso de Opioides/fisiopatologia , Ratos , Ratos Sprague-Dawley , Peixe-Zebra
18.
Am J Pharm Educ ; 84(9): ajpe7940, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-33012801

RESUMO

Objective. To assess the impact of a Doctor of Pharmacy (PharmD) capstone project on students' ability to conduct research and quality improvement, and to assess the feasibility of requiring projects in the core curriculum. Methods. Project proposals were solicited from faculty members and local colleagues, and students matched with an individual project and mentor. After developing a written research proposal in their third professional year, students completed the project with mentor oversight in their third and fourth professional years, culminating with a poster session and completion of a manuscript prior to graduation. Students' knowledge of biostatistics, research confidence, and attitudes regarding research were evaluated using a validated survey instrument. Students and mentors were surveyed for feedback, and students' publications and presentations were tracked. Results. Sixty-one students (97%) completed their projects on time. Students' confidence in their ability to understand and participate in research increased, but improvement in statistical knowledge and interest in conducting future research projects was minimal. Fifty-eight percent of students presented posters at national conferences. Thirteen (21%) published manuscripts in peer-reviewed journals. Students and mentors responded positively overall about the program and the associated time requirements. Conclusion. Requiring PharmD students to complete a capstone project prior to graduation was feasible and increased student confidence in their ability to participate in research and the number of student and faculty poster presentations and peer-reviewed publications. These findings support the consideration of the Academy that analysis, synthesis, and creation of new knowledge can be successfully implemented into the core PharmD curricula.


Assuntos
Pesquisa Biomédica , Competência Clínica , Educação em Farmácia , Mentores , Melhoria de Qualidade , Currículo , Humanos
19.
Pharmacol Biochem Behav ; 198: 173033, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32888972

RESUMO

Instrumental actions are initially goal-directed and driven by their associated outcome. However, with repeated experience habitual actions develop which are automated and efficient, as they are instead driven by antecedent stimuli. Dopamine is thought to facilitate the transition from goal-directed to habitual actions. This idea has been largely derived from evidence that psychostimulants accelerate the development of habitual actions. In the current study, we examined the impact of L-dopa (levodopa or L-dihydroxyphenylalanine), which also potentiates dopamine activity, on habitual learning. L-dopa was systemically administered prior to training rats to press a lever for a food outcome. When tested, L-dopa exposed animals were insensitive to changes in the value of the food outcome, and hence demonstrated accelerated habitual behavioral control compared to control animals that remained goal directed. We also showed that when N-acetylcysteine (NAC), an antioxidant and regulator of glutamate activity, was co-administered with L-dopa, it prevented the transition to habitual behavior; an effect demonstrated previously for cocaine. Therefore, this study establishes similarities between L-dopa and psychostimulants in both the development and prevention of habitual actions, and supports the notion that excess dopamine potentiates habitual learning. This finding extends the limited existing knowledge of the impact of L-dopa on learning and behavior, and has implications for neurological disorders where L-dopa is the primary treatment.


Assuntos
Acetilcisteína/farmacologia , Comportamento Animal/efeitos dos fármacos , Condicionamento Operante/efeitos dos fármacos , Levodopa/farmacologia , Animais , Antioxidantes/farmacologia , Comportamento Aditivo/tratamento farmacológico , Comportamento Aditivo/metabolismo , Dopamina/metabolismo , Dopaminérgicos/farmacologia , Ácido Glutâmico/metabolismo , Hábitos , Masculino , Atividade Motora/efeitos dos fármacos , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Ratos , Ratos Long-Evans
20.
Int J Soc Psychiatry ; 66(1): 76-83, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31623499

RESUMO

BACKGROUND: One integral way by which individuals in recovery pursue meaning and productivity in their lives is via employment. Unfortunately, the vast majority of individuals with serious mental illness (SMI) who express the desire to work remain unemployed. Families have the potential to play an important role in the domain of supported employment (SE), though may not have the knowledge or skills to do so. AIMS: This quantitative study aimed to better understand the perspectives of family members on the role of employment in recovery and the barriers faced by their loved ones in pursuing work. METHOD: Participants included 86 family members of individuals with SMI who were affiliated with their state NAMI Chapter and agreed to take part in an online survey. Wilcoxon signed-rank tests were used to determine meaningful differences between the highest and lowest ranked statements for each main research question. RESULTS: Family members recognize that employment is important to recovery and offers individuals with SMI a valued social role. Relative to other factors, financial independence and being employed in a competitive job were viewed as less important to recovery. The most salient barriers to employment included stable housing, need for transportation, concerns about losing benefits, low self-esteem, and medication side effects. CONCLUSIONS: While family members can appreciate the importance of SE and their loved ones' desire to work, they still tend to rank other factors as more integral to recovery. This underscores the need for additional education about the potential for employment to facilitate these other factors in recovery.


Assuntos
Readaptação ao Emprego , Família/psicologia , Transtornos Mentais/psicologia , Adulto , Idoso , Connecticut , Feminino , Humanos , Masculino , Transtornos Mentais/reabilitação , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Apoio Social , Inquéritos e Questionários
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