Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Cell Rep Methods ; 2(6): 100225, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35784651

RESUMO

The ability to precisely control transgene expression is essential for basic research and clinical applications. Adeno-associated viruses (AAVs) are non-pathogenic and can be used to drive stable expression in virtually any tissue, cell type, or species, but their limited genomic payload results in a trade-off between the transgenes that can be incorporated and the complexity of the regulatory elements controlling their expression. Resolving these competing imperatives in complex experiments inevitably results in compromises. Here, we assemble an optimized viral toolkit (VTK) that addresses these limitations and allows for efficient combinatorial targeting of cell types. Moreover, their modular design explicitly enables further refinements. We achieve this in compact vectors by integrating structural improvements of AAV vectors with innovative molecular tools. We illustrate the potential of this approach through a systematic demonstration of their utility for targeting cell types and querying their biology using a wide array of genetically encoded tools.


Assuntos
Vetores Genéticos , Sistema Nervoso , Transdução Genética , Vetores Genéticos/genética , Transgenes/genética
2.
Eur J Neurosci ; 32(1): 108-17, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20608969

RESUMO

Synaptic plasticity in the ventral tegmental area (VTA) is modulated by drugs of abuse and stress and is hypothesized to contribute to specific aspects of addiction. Both excitatory and inhibitory synapses on dopamine neurons in the VTA are capable of undergoing long-term changes in synaptic strength. While the strengthening or weakening of excitatory synapses in the VTA has been widely examined, the role of inhibitory synaptic plasticity in brain reward circuitry is less established. Here, we investigated the effects of drugs of abuse, as well as acute stress, on long-term potentiation of GABAergic synapses onto VTA dopamine neurons (LTP(GABA)). Morphine (10 mg/kg i.p.) reduced the ability of inhibitory synapses in midbrain slices to express LTP(GABA) both at 2 and 24 h after drug exposure but not after 5 days. Cocaine (15 mg/kg i.p.) impaired LTP(GABA) 24 h after exposure, but not at 2 h. Nicotine (0.5 mg/kg i.p.) impaired LTP(GABA) 2 h after exposure, but not after 24 h. Furthermore, LTP(GABA) was completely blocked 24 h following brief exposure to a stressful stimulus, a forced swim task. Our data suggest that drugs of abuse and stress trigger a common modification to inhibitory plasticity, synergizing with their collective effect at excitatory synapses. Together, the net effect of addictive substances or stress is expected to increase excitability of VTA dopamine neurons, potentially contributing to the early stages of addiction.


Assuntos
Drogas Ilícitas/farmacologia , Potenciação de Longa Duração , Neurônios , Estresse Fisiológico , Sinapses , Área Tegmentar Ventral , Analgésicos Opioides/farmacologia , Animais , Cocaína/farmacologia , Dopamina/metabolismo , Inibidores da Captação de Dopamina/farmacologia , Potenciação de Longa Duração/efeitos dos fármacos , Potenciação de Longa Duração/fisiologia , Morfina/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/ultraestrutura , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Técnicas de Patch-Clamp , Ratos , Ratos Sprague-Dawley , Receptores de Glucocorticoides/metabolismo , Sinapses/efeitos dos fármacos , Sinapses/fisiologia , Área Tegmentar Ventral/fisiologia , Área Tegmentar Ventral/ultraestrutura , Ácido gama-Aminobutírico/metabolismo
3.
Am J Addict ; 18(4): 259-71, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19444729

RESUMO

The development of drug addiction progresses along a continuum from acute drug use to compulsive use and drug seeking behavior. Many researchers have focused on identifying the physiological mechanisms involved in drug addiction in order to develop effective pharmacotherapies. Neuroplasticity, the putative mechanism underlying learning and memory, is modified by drugs of abuse and may contribute to the development of the eventual addicted state. Innovative treatments directly targeting these drug-induced changes in brain reward components and circuits may be efficacious in reducing drug use and relapse.


Assuntos
Dopamina/metabolismo , Rede Nervosa/metabolismo , Plasticidade Neuronal/fisiologia , Transtornos Relacionados ao Uso de Substâncias/metabolismo , Nível de Saúde , Humanos , Aprendizagem , Memória , Nicotina/farmacocinética , Agonistas Nicotínicos/farmacocinética , Núcleo Accumbens/metabolismo , Receptores de AMPA/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Recidiva , Recompensa
4.
Neuropsychopharmacology ; 34(7): 1829-42, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19194373

RESUMO

Drugs of abuse usurp the mechanisms underlying synaptic plasticity in areas of the brain, a process that may contribute to the development of addiction. We previously reported that GABAergic synapses onto dopaminergic neurons in the ventral tegmental area (VTA) exhibit long-term potentiation (LTP(GABA)) blocked by in vivo exposure to morphine. The presynaptically maintained LTP requires the retrogradely released nitric oxide (NO) to activate a presynaptic cGMP signaling cascade. Previous work reported that inhibitory GABA(A) receptor synapses in the VTA are also potentiated by cAMP. Here, we explored the interactions between cGMP-dependent (PKG) and cAMP-dependent (PKA) protein kinases in the regulation of these GABAergic synapses and LTP(GABA). Activation of PKG was required for NO-cGMP signaling and was also essential for the induction of synaptically elicited LTP(GABA), but not for its maintenance. Synapses containing GABA(A) receptors were potentiated by NO-cGMP signaling, whereas synapses containing GABA(B) receptors on the same cells were not potentiated. Moreover, although the cAMP-PKA system potentiated GABA(A) synapses, synaptically induced LTP(GABA) was independent of PKA activation. Surprisingly, however, raising cGMP levels saturated potentiation of these synapses, precluding further potentiation by cAMP and suggesting a convergent end point for both signaling pathways in the regulation of GABAergic release. We further found that persistent GABAergic synaptic modifications observed with in vivo morphine did not involve the presynaptic cAMP-PKA cascade. Taken together, our data suggest a synapse-specific role for NO-cGMP-PKG signaling pathway in opioid-induced plasticity of VTA GABA(A) synapses.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Potenciação de Longa Duração/fisiologia , Transdução de Sinais/fisiologia , Sinapses/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Animais Recém-Nascidos , Biofísica , AMP Cíclico/farmacologia , GMP Cíclico/farmacologia , Estimulação Elétrica/métodos , Inibidores Enzimáticos/farmacologia , Agonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , GABAérgicos/farmacologia , Técnicas In Vitro , Potenciação de Longa Duração/efeitos dos fármacos , Mesencéfalo/citologia , Modelos Biológicos , Neurônios/fisiologia , Técnicas de Patch-Clamp , Quinoxalinas/farmacologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Sinapses/efeitos dos fármacos
5.
Mol Pharmacol ; 72(6): 1557-66, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17895407

RESUMO

The CB1 cannabinoid receptor is a G-protein coupled receptor that has important physiological roles in synaptic plasticity, analgesia, appetite, and neuroprotection. We report the discovery of two structurally related CB1 cannabinoid receptor interacting proteins (CRIP1a and CRIP1b) that bind to the distal C-terminal tail of CB1. CRIP1a and CRIP1b are generated by alternative splicing of a gene located on chromosome 2 in humans, and orthologs of CRIP1a occur throughout the vertebrates, whereas CRIP1b seems to be unique to primates. CRIP1a coimmunoprecipitates with CB1 receptors derived from rat brain homogenates, indicating that CRIP1a and CB1 interact in vivo. Furthermore, in superior cervical ganglion neurons coinjected with CB1 and CRIP1a or CRIP1b cDNA, CRIP1a, but not CRIP1b, suppresses CB1-mediated tonic inhibition of voltage-gated Ca2+ channels. Discovery of CRIP1a provides the basis for a new avenue of research on mechanisms of CB1 regulation in the nervous system and may lead to development of novel drugs to treat disorders where modulation of CB1 activity has therapeutic potential (e.g., chronic pain, obesity, and epilepsy).


Assuntos
Proteínas de Transporte/fisiologia , Receptor CB1 de Canabinoide/metabolismo , Receptores de Canabinoides/fisiologia , Sequência de Aminoácidos , Animais , Canabinoides/metabolismo , Canabinoides/farmacologia , Proteínas de Transporte/genética , Linhagem Celular , Humanos , Proteínas com Domínio LIM , Proteínas de Membrana , Camundongos , Dados de Sequência Molecular , Ligação Proteica/fisiologia , Ratos , Receptor CB1 de Canabinoide/genética , Receptores de Canabinoides/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...