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1.
Neuropsychopharmacol Rep ; 43(1): 77-84, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36524248

RESUMO

Binge-like exposure to ethanol during the brain growth spurt triggers apoptotic neurodegeneration in multiple brain regions, including the retrosplenial cortex, a brain region that is part of the hippocampal-diencephalic-cingulate memory network. This is mediated, in part, by reduced Ca2+ influx through N-methyl-d-aspartate (NMDA) receptors followed by a decrease in the activation of pro-survival genes. Here, we tested whether a positive allosteric modulator of NMDA receptors could counteract the inhibitory effect of ethanol on developing retrosplenial cortex pyramidal neurons. We used patch-clamp electrophysiological techniques in acute slices from postnatal day 6-8 mice to test the effect of the positive allosteric modulator GNE-9278 on ethanol-induced inhibition of NMDA receptor function. GNE-9278 dose-dependently increased the amplitude, decay time, and total charge of NMDA excitatory postsynaptic currents. At a concentration of 5 µmol L-1 , GNE-9278 significantly reduced the 90 mmol L-1 ethanol-induced inhibition of NMDA excitatory postsynaptic current amplitude, decay time, and total charge. Current-clamp experiments showed that 5 µmol L-1 GNE-9278 ameliorated the 90 mmol L-1 ethanol-induced inhibition of synaptically-evoked action potential firing and compound excitatory postsynaptic potential amplitude. These findings indicate that positive allosteric modulators mitigate ethanol-induced hypofunction of NMDA receptors in developing cerebral cortex neurons, an effect that could ameliorate its pro-apoptotic effects during the late stages of fetal development.


Assuntos
Depressores do Sistema Nervoso Central , Etanol , Animais , Camundongos , Receptores de N-Metil-D-Aspartato/metabolismo , Giro do Cíngulo/metabolismo , N-Metilaspartato/farmacologia , Depressores do Sistema Nervoso Central/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Neurônios/metabolismo
2.
Psychopharmacology (Berl) ; 240(1): 171-183, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36538099

RESUMO

RATIONALE: One hallmark of addiction is an altered neuronal reward processing. In healthy individuals (HC), reduced activity in fronto-striatal regions including the insula has been observed when a reward anticipation task was performed repeatedly. This effect could indicate a desensitization of the neural reward system due to repetition. Here, we investigated this hypothesis in a cohort of patients with alcohol use disorder (AUD), who have been treated with baclofen or a placebo. The efficacy of baclofen in AUD patients has been shown to have positive clinical effects, possibly via indirectly affecting structures within the neuronal reward system. OBJECTIVES: Twenty-eight recently detoxified patients (13 receiving baclofen (BAC), 15 receiving placebo (PLA)) were investigated within a longitudinal, double-blind, and randomized pharmaco-fMRI design with an individually adjusted daily dosage of 30-270 mg. METHODS: Brain responses were captured by functional magnetic resonance imaging (fMRI) during reward anticipation while participating in a slot machine paradigm before (t1) and after 2 weeks of individual high-dose medication (t2). RESULTS: Abstinence rates were significantly higher in the BAC compared to the PLA group during the 12-week high-dose medication phase. At t1, all patients showed significant bilateral striatal activation. At t2, the BAC group showed a significant decrease in insular activation compared to the PLA group. CONCLUSIONS: By affecting insular information processing, baclofen might enable a more flexible neuronal adaptation during recurrent reward anticipation, which could resemble a desensitization as previously observed in HC. This result strengthens the modulation of the reward system as a potential mechanism of action of baclofen. TRIAL REGISTRATION: Identifier of the main trial (the BACLAD study) at clinical.gov: NCT0126665.


Assuntos
Alcoolismo , Depressores do Sistema Nervoso Central , Humanos , Baclofeno/farmacologia , Baclofeno/uso terapêutico , Alcoolismo/diagnóstico por imagem , Alcoolismo/tratamento farmacológico , Imageamento por Ressonância Magnética/métodos , Projetos Piloto , Etanol , Depressores do Sistema Nervoso Central/farmacologia , Poliésteres/farmacologia , Poliésteres/uso terapêutico , Recompensa , Antecipação Psicológica
3.
Int Rev Neurobiol ; 165: 17-34, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36208899

RESUMO

Coronavirus disease 2019 (Covid-19) caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection is primarily regarded as a respiratory disease; however, multisystemic involvement accompanied by a variety of clinical manifestations, including neurological symptoms, are commonly observed. There is, however, little evidence supporting SARS-CoV-2 infection of central nervous system cells, and neurological symptoms for the most part appear to be due to damage mediated by hypoxic/ischemic and/or inflammatory insults. In this chapter, we report evidence on candidate neuropathological mechanisms underlying neurological manifestations in Covid-19, suggesting that while there is mostly evidence against SARS-CoV-2 entry into brain parenchymal cells as a mechanism that may trigger Parkinson's disease and parkinsonism, that there are multiple means by which the virus may cause neurological symptoms.


Assuntos
COVID-19 , Depressores do Sistema Nervoso Central , Doenças do Sistema Nervoso , Doença de Parkinson , Sistema Nervoso Central , Humanos , SARS-CoV-2
4.
Nat Commun ; 13(1): 5521, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36130965

RESUMO

Assessing the neurological and behavioral effects of drugs is important in developing pharmacological treatments, as well as understanding the mechanisms associated with neurological disorders. Herein, we present a miniaturized, wireless neural probe system with the capability of delivering drugs for the real-time investigation of the effects of the drugs on both behavioral and neural activities in socially interacting mice. We demonstrate wireless drug delivery and simultaneous monitoring of the resulting neural, behavioral changes, as well as the dose-dependent and repeatable responses to drugs. Furthermore, in pairs of mice, we use a food competition assay in which social interaction was modulated by the delivery of the drug, and the resulting changes in their neural activities are analyzed. During modulated food competition by drug injection, we observe changes in neural activity in mPFC region of a participating mouse over time. Our system may provide new opportunities for the development of studying the effects of drugs on behaviour and neural activity.


Assuntos
Depressores do Sistema Nervoso Central , Neurofarmacologia , Animais , Encéfalo/fisiologia , Eletrofisiologia Cardíaca , Depressores do Sistema Nervoso Central/farmacologia , Camundongos , Neurônios/fisiologia
5.
J Opioid Manag ; 18(4): 377-383, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36052934

RESUMO

A recent review suggests minimal respiratory depression (RD) after perioperative methadone, while another identified RD in up to 37 percent of patients. A meta-analysis is equivocal. At our institution, five of 75 opioid naive patients (6.6 percent) given perioperative methadone received naloxone. We report three of these cases in detail. Two others were discovered during an electronic medical record search for opioid naïve patients who received methadone plus naloxone during their anesthesia care. Our five patients indicate that RD owing to methadone can occur with excessive perioperative adjuvant medications and/or in patients who are taking home central nervous system depressants. We define perioperative adjuvant medications as medications given by the anesthesiologist prior to induction and intraoperatively. The risks and benefits of perioperative methadone administration, specifically in patients who received post-operative naloxone, deserve further investigation.


Assuntos
Depressores do Sistema Nervoso Central , Transtornos Relacionados ao Uso de Opioides , Insuficiência Respiratória , Analgésicos Opioides/efeitos adversos , Depressores do Sistema Nervoso Central/uso terapêutico , Humanos , Metadona/efeitos adversos , Naloxona/efeitos adversos , Transtornos Relacionados ao Uso de Opioides/diagnóstico , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Insuficiência Respiratória/induzido quimicamente , Insuficiência Respiratória/diagnóstico , Insuficiência Respiratória/terapia
6.
Methods Mol Biol ; 2556: 287-302, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36175640

RESUMO

Three types of assays--colorimetric, fluorescent, and chemiluminescent--are used to determine the sialidase (neuraminidase: NA) activity of influenza viruses. The fluorescent assay is cost-effective and applicable for many laboratories and is, therefore, commonly used for global monitoring of the NA inhibitor susceptibility of influenza viruses. Here, I describe, in detail, protocols for the fluorescence-based NA activity assay and the NA inhibition assay, which are used to determine the NA activity and NA inhibitor susceptibility, respectively, of influenza viruses.


Assuntos
Depressores do Sistema Nervoso Central , Orthomyxoviridae , Antivirais/farmacologia , Bioensaio , Corantes , Inibidores Enzimáticos/farmacologia , Neuraminidase
7.
J Psychopharmacol ; 36(9): 1020-1035, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35912873

RESUMO

BACKGROUND: The benzodiazepine drug alprazolam, a fast-acting tranquiliser, cannot be prescribed on the National Health Service in the United Kingdom. Illicit alprazolam supply and consumption have increased. Concern about increasing numbers of alprazolam-related fatalities started circulating in 2018. However, statistics on this issue are very limited. This study examined patterns in such mortality in Scotland. METHODS: Statistics on deaths where alprazolam was mentioned in the 'cause of death' were obtained from official mortality registers. Anonymised Scottish case-level data were obtained. Data were examined in respect of the characteristics of decedents and deaths using descriptive statistics. RESULTS: Scotland registered 370 deaths in 2004-2020; 366 of these occurred in 2015-2020: most involved males (77.1%); mean age 39.0 (SD 12.6) years. The principal underlying cause of death was accidental poisoning: opiates/opioids (77.9%); sedatives/hypnotics (15.0%). Two deaths involved alprazolam alone. Main drug groups implicated: opiates/opioids (94.8%), 'other benzodiazepines' (67.2%), gabapentinoids (42.9%), stimulants (30.1%), antidepressants (15.0%). Two-thirds (64.2%) involved combinations of central nervous system (CNS) depressants. DISCUSSION: Alprazolam-related deaths are likely due to an increasing illicit supply. The fall in deaths in 2019-2020 is partially due to increased use of designer benzodiazepines. Treatment for alprazolam dependence is growing. Clinicians need to be aware of continuing recreational alprazolam use. When such consumption occurs with CNS depressants, overdose and death risks increase. CONCLUSIONS: More awareness of alprazolam contributing to deaths, especially in conjunction with other CNS depressants, is needed by consumers and clinicians. Improved monitoring of illicit supplies could identify emerging issues of medicines' abuse.


Assuntos
Depressores do Sistema Nervoso Central , Alcaloides Opiáceos , Adulto , Alprazolam/efeitos adversos , Analgésicos Opioides , Benzodiazepinas/efeitos adversos , Humanos , Hipnóticos e Sedativos , Masculino , Escócia/epidemiologia , Medicina Estatal
8.
Drugs Aging ; 39(9): 729-738, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35945484

RESUMO

BACKGROUND: Co-prescription of opioids with other central nervous system (CNS) depressants is common but the combination may increase the risk for adverse events such as falls and fractures, particularly among older adults. We explored the risk of fall- or fracture-related hospital visits after opioid initiation among older adults with varying degrees of concomitant CNS depressant burden. METHODS: We used population-based administrative health data from Ontario, Canada, to examine the relationship between hospital visits for falls or fractures at different levels of CNS burden among individuals aged 66 and older who started prescription opioids between March 1, 2008, and March 31, 2019. For comparison, we identified individuals starting prescription non-steroidal anti-inflammatory drugs (NSAIDs). The outcome was a hospital visit for falls or fractures within 14 days after starting analgesic therapy. We stratified the cohort according to additional CNS burden: none, low (one concurrent CNS depressant drug class) and high (≥ 2 concurrent CNS depressant classes) on the index date. We balanced opioid and NSAID recipients using inverse probability of treatment weighting and reported weighted hazard ratios from Cox proportional hazards models. We then used pairwise comparisons to determine differences between hazard ratios at different levels of CNS burden. RESULTS: The cohort included 1,066,692 older adults, with 562,692 new opioid recipients and 504,000 new NSAID recipients. Among opioid recipients, 83 % had no additional CNS burden, 13 % had low burden and 4 % had high burden. The short-term rate of falls or fractures for new opioid recipients increased by CNS burden from 97 per 1000 person-years (no burden) to 233 per 1000 person-years (high CNS burden). Opioid recipients had a similarly elevated hazard of falls or fractures within each CNS burden level compared to NSAID recipients (adjusted hazard ratio [aHR] 1.62, 95 % CI 1.50-1.76 for no burden; aHR 1.69, 95 % CI 1.45-1.97 for low burden; aHR 1.40, 95 % CI 1.08-1.82 for high burden). CONCLUSION: Among older adults, initiation of opioids is associated with an increased hazard of falls; however, this hazard is not modified by different levels of CNS depressant burden. This suggests that it remains important for physicians, patients, and caregivers to be vigilant when starting new opioid therapy regardless of other CNS medications taken concurrently.


Assuntos
Depressores do Sistema Nervoso Central , Fraturas Ósseas , Idoso , Analgésicos Opioides , Anti-Inflamatórios não Esteroides , Fármacos do Sistema Nervoso Central , Fraturas Ósseas/induzido quimicamente , Fraturas Ósseas/epidemiologia , Humanos , Ontário/epidemiologia
9.
Cells ; 11(15)2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35954216

RESUMO

MicroRNAs (miRNAs) are small noncoding RNAs that play a prominent role in post-transcriptional gene regulation mechanisms in the brain tuning synaptic plasticity, memory formation, and cognitive functions in physiological and pathological conditions [...].


Assuntos
Depressores do Sistema Nervoso Central , MicroRNAs , Doenças do Sistema Nervoso , Regulação da Expressão Gênica , Humanos , MicroRNAs/metabolismo , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/metabolismo , Plasticidade Neuronal/fisiologia
10.
Adv Exp Med Biol ; 1370: 325-331, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35882807

RESUMO

This article briefly describes the trophic actions of taurine in the developing brain, contribution of taurine to the volume regulation of brain cells, and the interference of taurine with the synaptic amino acid receptors. Finally the possible use of taurine as a drug is discussed in various pathological states of the brain.When we searched material for this review, we got almost 4000 articles from the PubMed when using the terms "taurine and brain." It is impossible to review all these articles. We must only select some items from this plethora. A few years ago, several exhaustive reviews have appeared on this topic. The readers are referred to them and their references for more detailed information of the earlier studies (Oja and Kontro, Taurine. In: Lajtha A (ed) Handbook of neurochemistry, vol 3, 2nd edn. Plenum Press, New York, pp 501-533, 1983; Huxtable, Taurine and the oxidative metabolism of cysteine. Biochemistry of sulfur. Plenum Press, New York, pp 121-198, 1986; Prog Neurobiol 32:471-533, 1989; Physiol Rev 72:101-163, 1992; Sturman, Physiol Rev 73:119-147, 1993; Oja and Saransaari, Taurine. In: Lajtha A, Oja SS, Saransaari P, Schousboe A (eds) Handbook of neurochemistry and molecular neurobiology. Amino acids and peptides in the nervous system, vol 3, 3rd edn. Springer, Berlin, pp 155-206, 2007; Saransaari and Oja, Taurine in neurotransmission. In: Lajtha A, Vizi ES (eds) Handbook of neurochemistry and molecular neurobiology. Neurotransmitter systems, vol 6, 3rd edn. Springer, Berlin, pp 155-206, 2008). We now focus mainly on more recent articles published during the few last years.


Assuntos
Depressores do Sistema Nervoso Central , Taurina , Aminoácidos , Encéfalo/metabolismo , Cisteína , Taurina/metabolismo
11.
Int J Mol Sci ; 23(9)2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35562999

RESUMO

Glyphosate, a non-selective systemic biocide with broad-spectrum activity, is the most widely used herbicide in the world. It can persist in the environment for days or months, and its intensive and large-scale use can constitute a major environmental and health problem. In this systematic review, we investigate the current state of our knowledge related to the effects of this pesticide on the nervous system of various animal species and humans. The information provided indicates that exposure to glyphosate or its commercial formulations induces several neurotoxic effects. It has been shown that exposure to this pesticide during the early stages of life can seriously affect normal cell development by deregulating some of the signaling pathways involved in this process, leading to alterations in differentiation, neuronal growth, and myelination. Glyphosate also seems to exert a significant toxic effect on neurotransmission and to induce oxidative stress, neuroinflammation and mitochondrial dysfunction, processes that lead to neuronal death due to autophagy, necrosis, or apoptosis, as well as the appearance of behavioral and motor disorders. The doses of glyphosate that produce these neurotoxic effects vary widely but are lower than the limits set by regulatory agencies. Although there are important discrepancies between the analyzed findings, it is unequivocal that exposure to glyphosate produces important alterations in the structure and function of the nervous system of humans, rodents, fish, and invertebrates.


Assuntos
Depressores do Sistema Nervoso Central , Herbicidas , Síndromes Neurotóxicas , Animais , Glicina/análogos & derivados , Glicina/química , Glicina/toxicidade , Herbicidas/química , Herbicidas/toxicidade , Síndromes Neurotóxicas/etiologia , Síndromes Neurotóxicas/metabolismo
12.
Biochem Biophys Res Commun ; 609: 141-148, 2022 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-35429681

RESUMO

Histamine is synthesised from l-histidine through the catalysis of histidine decarboxylase (HDC). In the central nervous system (CNS), histamine is exclusively produced in histaminergic neurons located in the posterior hypothalamus and controls various CNS functions. Although histidine was known as a precursor of histamine, the impact of oral histidine intake on brain histamine concentration and brain function has not been fully elucidated. In the present study, we aimed to elucidate the importance of oral histidine supplementation in the histaminergic nervous system and working memory in stressful conditions. First, we confirmed that sleep deprivation by water-floor stress in male mice increased histamine consumption and resulted in histamine reduction and impaired working memory in the Y-maze test. This memory impairment was rescued by intracerebroventricular injection of histamine and histidine, indicating that oral histidine intake could also improve memory function. Next, we examined the impact of histidine intake on brain histamine concentration and neuronal activity. Histidine intake increased extracellular histamine concentration around the prefrontal cortex (PFC) and the basal forebrain (BF), leading to a robust increase in the number of c-fos-positive cells around these areas. Finally, we investigated the beneficial effects of histidine intake on working memory. Histidine supplementation alleviated impaired memory function induced by sleep deprivation. This beneficial effect of histidine on memory was cancelled by intracerebroventricular injection of the HDC inhibitor α-fluoromethylhistidine. These results demonstrate that oral histidine intake replenishes brain histamine and leads to the recovery of impaired working memory induced by sleep deprivation through histaminergic activation.


Assuntos
Depressores do Sistema Nervoso Central , Histidina , Animais , Histamina , Histidina/farmacologia , Histidina Descarboxilase , Masculino , Memória de Curto Prazo , Camundongos , Neurônios , Privação do Sono
13.
Neuron ; 110(8): 1275-1277, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35447095

RESUMO

Communication between the nervous system and immune system is important for regulating immunity in health and disease. Yu et al. (2022) show that neuropeptide Y and its homolog NPF serve as a "language" to facilitate crosstalk between these two systems across species, enabling neurons to downregulate harmful immune responses.


Assuntos
Depressores do Sistema Nervoso Central , Neuropeptídeos , Sistema Nervoso , Neurônios , Neuropeptídeo Y
14.
Mikrochim Acta ; 189(3): 100, 2022 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-35152330

RESUMO

Falsified medicines and healthcare supplements provide a major risk to public health and thus early identification is critical. Although a host of analytical approaches have been used to date, they are limited, as they require extensive sample preparation, are semi-quantitative and/or are inaccessible to low- and middle-income countries. Therefore, for the first time, we report a simple total analysis system which can rapidly and accurately detect falsified medicines and healthcare supplements. We fabricated a poly-lactic acid (PLA) pestle and mortar and using a commercial 3D printer, then made carbon black/PLA (CB/PLA) electrodes in the base of the mortar using a 3D printing pen to make an electrochemical cell. The pestle and mortar were able to crush and grind the tablets into a fine powder to the same consistency as a standard laboratory pestle and mortar. Using melatonin tablets to characterise the device, the 3D-printed pestle and mortar was able to detect the concentration of melatonin in the presence of insoluble excipients. The calibration plot showed a linear response from 37.5 to 300 µg/mL, where the limit of detection was 7 µg/mL. Electrochemical treatment was able to regenerate the CB/PLA working electrode allowing for repeated use of the device. In a blinded study, the device was able to accurately determine falsified melatonin tablets with recovery percentages between 101% and 105%. This was comparable to HPLC measurements. Overall, these findings highlight that our 3D-printed electrochemical pestle and mortar is an accessible and effective total analysis system that can have the ability to identify falsified medicines and healthcare supplements in remote locations.


Assuntos
Depressores do Sistema Nervoso Central/análise , Técnicas Eletroquímicas , Melatonina/análise , Poliésteres/química , Impressão Tridimensional , Eletrodos , Legislação de Medicamentos , Comprimidos
16.
Dig Dis Sci ; 67(2): 524-535, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-33555515

RESUMO

OBJECTIVE: Alcohol consumption is always the main cause of acute pancreatitis (AP). It has been reported that alcohol exerts direct damage to the pancreas. However, the specific role of alcohol during AP needs to be investigated. This study aims to examine the effects of alcohol in cerulein-induced AP and the role of the AMPK pathway. METHODS: Human subjects from operations, cerulein-induced AP rat, and cerulein-stimulated AR42J cell line were enrolled in this study. Electron microscopy was employed for observation of cell morphology, immunohistochemistry for identification of cells, ELISA for detection of inflammation factors, Annexin V/PI double staining for evaluation of cell apoptosis, immunofluorescence for assessment of autophagic flux, oil red O staining for examination of lipid droplet accumulation, and Western blot for measurement of expressions of proteins related to autophagy, apoptosis, and AMPK signal pathway. PI3K inhibitor 3-MA and AMPK inhibitor BML-275 were utilized for investigation of the relationship between impaired autophagic flux and the AMPK pathway by inhibiting or stimulating the formation of autophagosome. RESULTS: Alcohol consumption caused lipid droplet accumulation in the pancreas, and it also activated AMPK signaling pathway, thus aggravating the autophagic flux during AP. Alcohol up-regulated the expressions of anti-apoptotic proteins during the induction of AP to inhibit cell apoptosis and enhance cell necrosis. Inhibition of autophagosome formation by AMPK inhibitor BML-275 ameliorated the decreased cell viability caused by alcohol and cerulein in vitro. CONCLUSION: Alcohol aggravates AP progression by impairing autophagic flux and enhancing cell autophagy through the AMPK signaling pathway.


Assuntos
Adenilato Quinase/metabolismo , Autofagia/efeitos dos fármacos , Depressores do Sistema Nervoso Central/farmacologia , Etanol/farmacologia , Pâncreas/efeitos dos fármacos , Pancreatite Alcoólica/metabolismo , Adenilato Quinase/antagonistas & inibidores , Adenilato Quinase/efeitos dos fármacos , Animais , Linhagem Celular , Ceruletídeo/toxicidade , Humanos , Pancreatite/induzido quimicamente , Pancreatite/metabolismo , Pancreatite/patologia , Pancreatite Alcoólica/patologia , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Ratos , Transdução de Sinais
17.
Behav Brain Res ; 421: 113726, 2022 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-34954300

RESUMO

In order to further elucidate the role of mesolimbic peptides in the expression of ethanol reward, the present study investigated the effects of ghrelin and glucagon-like peptide-1 (GLP-1) on ethanol intake, in addition to ethanol intake stimulated by systemic d-amphetamine or cocaine treatment. While a number of studies suggest that ghrelin plays an important role in mesolimbic reward, emerging data now indicate that GLP-1 receptor mechanisms inhibit reward signaling, possibly by directly or indirectly inhibiting ghrelinergic activity within the mesolimbic system. In the present study all rats were initially habituated to a 6% ethanol solution. We then demonstrated that intraperitoneal injections of d-amphetamine and cocaine increased ethanol intake compared to the vehicle condition. In subsequent testing we examined the effects of ventral tegmental area (VTA) ghrelin or vehicle paired with a fixed dose of d-amphetamine or vehicle. In separate rats we then investigated the impact of the GLP-1 agonist exendin-4 (Ex-4), injected into the VTA, on ethanol intake alone, or when Ex-4 was co-administered with d-amphetamine or cocaine. Our results indicated that VTA ghrelin significantly increased ethanol intake, and most importantly, potentiated the effect of d-amphetamine and cocaine on ethanol consumption. Conversely, VTA Ex-4 inhibited ethanol intake and antagonized the stimulatory effect of d-amphetamine and cocaine on ethanol consumption. In a final study we further demonstrated that VTA Ex-4 treatment significantly inhibited the combined stimulatory effects of ghrelin paired with d-amphetamine or ghrelin paired with cocaine. Overall our findings are consistent with a critical role for both ghrelin and GLP-1 receptor mechanisms in mesolimbic ethanol reward circuitry. Moreover, our results further suggest that ghrelin and GLP-1 modulate the stimulatory effect of psychostimulants on ethanol intake.


Assuntos
Consumo de Bebidas Alcoólicas , Comportamento Animal/efeitos dos fármacos , Depressores do Sistema Nervoso Central/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Cocaína/farmacologia , Dextroanfetamina/farmacologia , Etanol/farmacologia , Grelina/farmacologia , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Área Tegmentar Ventral/efeitos dos fármacos , Animais , Depressores do Sistema Nervoso Central/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Cocaína/administração & dosagem , Dextroanfetamina/administração & dosagem , Etanol/administração & dosagem , Exenatida/farmacologia , Grelina/administração & dosagem , Peptídeo 1 Semelhante ao Glucagon/agonistas , Incretinas/farmacologia , Masculino , Ratos , Ratos Sprague-Dawley
18.
J Neurochem ; 160(4): 469-481, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34928513

RESUMO

Alcohol exposure alters the signaling of the serotoninergic system, which is involved in alcohol consumption, reward, and dependence. In particular, dysregulation of serotonin receptor type 1A (5-HT1AR) is associated with alcohol intake and withdrawal-induced anxiety-like behavior in rodents. However, how ethanol regulates 5-HT1AR activity and cell surface availability remains elusive. Using neuroblastoma 2a cells stably expressing human 5-HT1ARs tagged with hemagglutinin at the N-terminus, we found that prolonged ethanol exposure (18 h) reduced the basal surface levels of 5-HT1ARs in a concentration-dependent manner. This reduction is attributed to both enhanced receptor internalization and attenuated receptor recycling. Moreover, constitutive 5-HT1AR internalization in ethanol naïve cells was blocked by concanavalin A (ConA) but not nystatin, suggesting clathrin-dependent 5-HT1AR internalization. In contrast, constitutive 5-HT1AR internalization in ethanol-treated cells was blocked by nystatin but not by ConA, indicating that constitutive 5-HT1AR internalization switched from a clathrin- to a caveolin-dependent pathway. Dynasore, an inhibitor of dynamin, blocked 5-HT1AR internalization in both vehicle- and ethanol-treated cells. Furthermore, ethanol exposure enhanced the activity of dynamin I via dephosphorylation and reduced myosin Va levels, which may contribute to increased internalization and reduced recycling of 5-HT1ARs, respectively. Our findings suggest that prolonged ethanol exposure not only alters the endocytic trafficking of 5-HT1ARs but also the mechanism by which constitutive 5-HT1AR internalization occurs.


Assuntos
Depressores do Sistema Nervoso Central/farmacologia , Etanol/farmacologia , Receptor 5-HT1A de Serotonina/efeitos dos fármacos , Receptor 5-HT1A de Serotonina/metabolismo , Linhagem Celular , Clatrina/metabolismo , Concanavalina A/farmacologia , Relação Dose-Resposta a Droga , Dinaminas/metabolismo , Endocitose , Humanos , Hidrazonas/farmacologia , Nistatina/farmacologia , Antagonistas do Receptor 5-HT1 de Serotonina/farmacologia , Proteínas rab de Ligação ao GTP/metabolismo
19.
Neuropharmacology ; 206: 108934, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-34933049

RESUMO

Genetic differences in cerebellar sensitivity to alcohol (EtOH) influence EtOH consumption phenotype in animal models and contribute to risk for developing an alcohol use disorder in humans. We previously determined that EtOH enhances cerebellar granule cell (GC) tonic GABAAR currents in low EtOH consuming rodent genotypes, but suppresses it in high EtOH consuming rodent genotypes. Moreover, pharmacologically counteracting EtOH suppression of GC tonic GABAAR currents reduces EtOH consumption in high alcohol consuming C57BL/6J (B6J) mice, suggesting a causative role. In the low EtOH consuming rodent models tested to date, EtOH enhancement of GC tonic GABAAR currents is mediated by inhibition of neuronal nitric oxide synthase (nNOS) which drives increased vesicular GABA release onto GCs and a consequent enhancement of tonic GABAAR currents. Consequently, genetic variation in nNOS expression across rodent genotypes is a key determinant of whether EtOH enhances or suppresses tonic GABAAR currents, and thus EtOH consumption. We used behavioral, electrophysiological, and immunocytochemical techniques to further explore the relationship between EtOH consumption and GC GABAAR current responses in C57BL/6N (B6N) mice. B6N mice consume significantly less EtOH and achieve significantly lower blood EtOH concentrations than B6J mice, an outcome not mediated by differences in taste. In voltage-clamped GCs, EtOH enhanced the GC tonic current in B6N mice but suppressed it in B6J mice. Immunohistochemical and electrophysiological studies revealed significantly higher nNOS expression and function in the GC layer of B6N mice compared to B6Js. Collectively, our data demonstrate that despite being genetically similar, B6N mice consume significantly less EtOH than B6J mice, a behavioral difference paralleled by increased cerebellar nNOS expression and opposite EtOH action on GC tonic GABAAR currents in each genotype.


Assuntos
Consumo de Bebidas Alcoólicas/fisiopatologia , Alcoolismo/fisiopatologia , Depressores do Sistema Nervoso Central/farmacologia , Córtex Cerebelar , Fenômenos Eletrofisiológicos , Etanol/farmacologia , Óxido Nítrico Sintase Tipo I , Receptores de GABA-A , Animais , Comportamento Animal/fisiologia , Depressores do Sistema Nervoso Central/administração & dosagem , Córtex Cerebelar/efeitos dos fármacos , Córtex Cerebelar/metabolismo , Modelos Animais de Doenças , Fenômenos Eletrofisiológicos/efeitos dos fármacos , Fenômenos Eletrofisiológicos/fisiologia , Etanol/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL/genética , Óxido Nítrico Sintase Tipo I/efeitos dos fármacos , Óxido Nítrico Sintase Tipo I/metabolismo , Receptores de GABA-A/efeitos dos fármacos , Receptores de GABA-A/fisiologia , Especificidade da Espécie
20.
Neuropharmacology ; 206: 108937, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-34965406

RESUMO

Although the pharmacological and behavioural interactions between cocaine and alcohol are well established, less is known about how polyconsumption of these drugs affects the neurotransmitter systems involved in their psychoactive effects and in particular, in the process of addiction. Here, rats of both sexes at two stages of development were studied under a chronic regime of intravenous cocaine and/or alcohol administration. Brain samples from the medial prefrontal cortex, nucleus accumbens, hippocampus and amygdala were extracted to analyse the mRNA expression of genes encoding subunits of the GABA, NMDA and AMPA receptors, as well as the expression of the CB1 receptor, and that of enzymes related to the biosynthesis and degradation of endocannabinoids. Moreover, two synaptic scaffold proteins related to GABA and NMDA receptors, gephyrin and PSD-95, were quantified in Western blots. Significant interactions between cocaine and alcohol were common, affecting the GABAergic and endocannabinoid systems in the medial prefrontal cortex and amygdala of young adults, whereas such interactions were evident in the glutamatergic and endocannabinoid systems in adults, as well as a more pronounced sex effect. Significant interactions between these drugs affecting the scaffold proteins were evident in the medial prefrontal cortex and nucleus accumbens of young adults, and in the nucleus accumbens and amygdala of adults, but not in the hippocampus. These results highlight the importance of considering the interactions between cocaine and alcohol on neurotransmitter systems in the context of polyconsumption, specifically when treating problems of abuse of these two substances.


Assuntos
Depressores do Sistema Nervoso Central/farmacologia , Cérebro/efeitos dos fármacos , Cocaína/farmacologia , Inibidores da Captação de Dopamina/farmacologia , Etanol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Receptores de AMPA/efeitos dos fármacos , Receptores de Canabinoides/efeitos dos fármacos , Receptores de GABA/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Fatores Etários , Animais , Depressores do Sistema Nervoso Central/administração & dosagem , Cocaína/administração & dosagem , Inibidores da Captação de Dopamina/administração & dosagem , Interações Medicamentosas , Etanol/administração & dosagem , Feminino , Masculino , Ratos , Caracteres Sexuais
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