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1.
Mol Psychiatry ; 20(1): 48-55, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25349171

RESUMO

Conventional antidepressants require 2-8 weeks for a full clinical response. In contrast, two rapidly acting antidepressant interventions, low-dose ketamine and sleep deprivation (SD) therapy, act within hours to robustly decrease depressive symptoms in a subgroup of major depressive disorder (MDD) patients. Evidence that MDD may be a circadian-related illness is based, in part, on a large set of clinical data showing that diurnal rhythmicity (sleep, temperature, mood and hormone secretion) is altered during depressive episodes. In a microarray study, we observed widespread changes in cyclic gene expression in six regions of postmortem brain tissue of depressed patients matched with controls for time-of-death (TOD). We screened 12 000 transcripts and observed that the core clock genes, essential for controlling virtually all rhythms in the body, showed robust 24-h sinusoidal expression patterns in six brain regions in control subjects. In MDD patients matched for TOD with controls, the expression patterns of the clock genes in brain were significantly dysregulated. Some of the most robust changes were seen in anterior cingulate (ACC). These findings suggest that in addition to structural abnormalities, lesion studies, and the large body of functional brain imaging studies reporting increased activation in the ACC of depressed patients who respond to a wide range of therapies, there may be a circadian dysregulation in clock gene expression in a subgroup of MDDs. Here, we review human, animal and neuronal cell culture data suggesting that both low-dose ketamine and SD can modulate circadian rhythms. We hypothesize that the rapid antidepressant actions of ketamine and SD may act, in part, to reset abnormal clock genes in MDD to restore and stabilize circadian rhythmicity. Conversely, clinical relapse may reflect a desynchronization of the clock, indicative of a reactivation of abnormal clock gene function. Future work could involve identifying specific small molecules capable of resetting and stabilizing clock genes to evaluate if they can rapidly relieve symptoms and sustain improvement.


Assuntos
Antidepressivos/uso terapêutico , Proteínas CLOCK/genética , Transtornos Cronobiológicos/complicações , Transtornos Cronobiológicos/genética , Transtorno Depressivo Maior , Animais , Transtorno Depressivo Maior/etiologia , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/terapia , Antagonistas de Aminoácidos Excitatórios/uso terapêutico , Giro do Cíngulo/metabolismo , Humanos , Ketamina/uso terapêutico , Privação do Sono
2.
Mol Psychiatry ; 16(6): 634-46, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20386568

RESUMO

Several studies have proposed that brain glutamate signaling abnormalities and glial pathology have a role in the etiology of major depressive disorder (MDD). These conclusions were primarily drawn from post-mortem studies in which forebrain brain regions were examined. The locus coeruleus (LC) is the primary source of extensive noradrenergic innervation of the forebrain and as such exerts a powerful regulatory role over cognitive and affective functions, which are dysregulated in MDD. Furthermore, altered noradrenergic neurotransmission is associated with depressive symptoms and is thought to have a role in the pathophysiology of MDD. In the present study we used laser-capture microdissection (LCM) to selectively harvest LC tissue from post-mortem brains of MDD patients, patients with bipolar disorder (BPD) and from psychiatrically normal subjects. Using microarray technology we examined global patterns of gene expression. Differential mRNA expression of select candidate genes was then interrogated using quantitative real-time PCR (qPCR) and in situ hybridization (ISH). Our findings reveal multiple signaling pathway alterations in the LC of MDD but not BPD subjects. These include glutamate signaling genes, SLC1A2, SLC1A3 and GLUL, growth factor genes FGFR3 and TrkB, and several genes exclusively expressed in astroglia. Our data extend previous findings of altered glutamate, astroglial and growth factor functions in MDD for the first time to the brainstem. These findings indicate that such alterations: (1) are unique to MDD and distinguishable from BPD, and (2) affect multiple brain regions, suggesting a whole-brain dysregulation of such functions.


Assuntos
Transtorno Depressivo Maior/patologia , Regulação da Expressão Gênica , Ácido Glutâmico/metabolismo , Locus Cerúleo/metabolismo , Neuroglia/metabolismo , Transdução de Sinais/fisiologia , Adolescente , Adulto , Idoso , Feminino , Perfilação da Expressão Gênica/métodos , Proteínas de Transporte de Glutamato da Membrana Plasmática , Ácido Glutâmico/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Locus Cerúleo/patologia , Masculino , Microdissecção , Pessoa de Meia-Idade , Modelos Biológicos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos/métodos , RNA Mensageiro/metabolismo , Adulto Jovem
3.
Acta Med Indones ; 44(4): 284-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23314968

RESUMO

AIM: to asses the role of Microsomal Glutathione S-Transferase1 (MGST1) gene as one of enzym metabolism that plays in enviromental factor. METHODS: using case-control study, subjects with age less than 50 years were collected from teaching hospital Makassar between 2008-2010. Frozen or routinely processed tumour samples biopsy and peripheral blood were obtained from 35 CRC patients undergoing surgery and endoscopic examination with 61 subject as control. CRC cases were diagnosis by clinical examination and confirm by histopathology without familial aggregation of CRC. DNA resequencing was conducted for the 3 kb genomic DNA region MGST1 using PCR-restriction fragment length polymorphism (PCR-RFLP). RESULTS: from 96 subject, two varian single nucleotide polymorphisms (SNPs) 16454T>G and 16416G>A MGST1 were identified. Significant CRC association (p= 0.047) was detected in GG genotipe SNP 16454T>G MGST1 with 3.5 fold risk (95% confidence interval (CI) 0.962-13.191). CONCLUSION: the results suggest that MGST1 gene polymorphisms as one of environment gene may contribute to CRC risk in younger age (<50 years old).


Assuntos
Neoplasias Colorretais/genética , Glutationa Transferase/genética , Polimorfismo de Nucleotídeo Único , Adulto , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Indonésia , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
4.
Cureus ; 14(2): e21895, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35273856

RESUMO

Brucellosis is a common zoonotic infection endemic to certain areas of the Mediterranean, Middle East, Central America, and Sub-Saharan Africa. We present a case of brucellosis in a patient who recently traveled to Grenada and returned to the United States with a wide degree of symptoms. This case explores the etiology, clinical presentation, investigation, and treatment of brucellosis. Though a patient's clinical presentation may be non-specific, the recognition of potential etiologies may aid in empirically treating the infection prior to laboratory confirmation.

5.
Cureus ; 13(2): e13593, 2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33815993

RESUMO

Malignant pleural effusion (MPE) due to renal cell carcinoma (RCC) is extremely rare, accounting for only 1%-2% of all malignant pleural effusions. This paper presents a case report of a 56-year-old male who presented with a chief complaint of bilateral flank pain with dyspnea and was diagnosed with RCC via immunopathologic pleural fluid analysis and who persistently had recurrent large volume pleural effusion. A 56-year-old male who had a recent admission for dyspnea secondary to a right-sided pleural effusion underwent thoracentesis and returned to the hospital for his worsening shortness of breath. He was found to have recurrent pleural effusion. Thoracentesis studies revealed an exudative pleural effusion positive for malignant cells showing adenocarcinoma, which had an immunopathologic profile (WT-1 and PAX8) favoring an adenocarcinoma of kidney origin. The patient underwent chest tube placement, followed by chemical pleurodesis with 4.3 L of bloody fluid drained immediately. Subsequent x-rays taken while the chest tube was in place showed worsening reaccumulating pleural effusion. A repeat CT scan showed a large right pleural effusion with loculated collections. The patient then underwent right video-assisted thoracoscopic surgery, which revealed a loculated effusion with pleural carcinomatosis that was biopsy-positive for RCC. This report presents a rare case displaying how RCC pleural carcinomatosis can cause a patient to present with dyspnea secondary to a pleural effusion, which was revealed to be RCC upon fluid cytology and immunohistopathology studies. This case demonstrates that RCC can cause recurrent large volume MPE, which has not been widely reported in contemporary literature.

6.
Eur J Neurosci ; 31(1): 79-89, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20104651

RESUMO

Hippocampal plasticity (e.g. neurogenesis) likely plays an important role in maintaining addictive behavior and/or relapse. This study assessed whether rats with differential propensity to drug-seeking behavior, bred Low-Responders (bLR) and bred High-Responders (bHR) to novelty, show differential neurogenesis regulation after cocaine exposure. Using specific immunological markers, we labeled distinct populations of adult stem cells in the dentate gyrus at different time-points of the cocaine sensitization process; Ki-67 for newly born cells, NeuroD for cells born partway, and 5-bromo-2'-deoxyuridine for older cells born prior to sensitization. Results show that: (i) bHRs exhibited greater psychomotor response to cocaine than bLRs; (ii) acute cocaine did not alter cell proliferation in bLR/bHR rats; (iii) chronic cocaine decreased cell proliferation in bLRs only, which became amplified through the course of abstinence; (iv) neither chronic cocaine nor cocaine abstinence affected the survival of immature neurons in either phenotype; (v) cocaine abstinence decreased survival of mature neurons in bHRs only, an effect that paralleled the greater psychomotor response to cocaine; and (vi) cocaine treatment did not affect the ratio of neurons to glia in bLR/bHR rats as most cells differentiated into neurons in both lines. Thus, cocaine exerts distinct effects on neurogenesis in bLR vs. bHR rats, with a decrease in the birth of new progenitor cells in bLRs and a suppression of the survival of new neurons in bHRs, which likely leads to an earlier decrease in formation of new connections. This latter effect in bHRs could contribute to their enhanced degree of cocaine-induced psychomotor behavioral sensitization.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/fisiopatologia , Cocaína/farmacologia , Giro Denteado/efeitos dos fármacos , Inibidores da Captação de Dopamina/farmacologia , Neurogênese/efeitos dos fármacos , Células-Tronco Adultas/efeitos dos fármacos , Células-Tronco Adultas/fisiologia , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Cocaína/administração & dosagem , Giro Denteado/fisiopatologia , Modelos Animais de Doenças , Inibidores da Captação de Dopamina/administração & dosagem , Hipocampo/efeitos dos fármacos , Hipocampo/fisiopatologia , Masculino , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Neurogênese/fisiologia , Neuroglia/efeitos dos fármacos , Neuroglia/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ratos , Ratos Endogâmicos , Especificidade da Espécie , Fatores de Tempo
7.
Cureus ; 12(12): e12331, 2020 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-33520529

RESUMO

Severe malaria due to the infection of Plasmodium falciparum is a critical infection that may lead to multisystem abnormalities if not promptly and adequately treated. We present a case of severe malaria in a patient recently repatriated from Conakry, Guinea, West Africa, marooned during the recent coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). While the direct costs of the SARS-CoV-2 pandemic and its indirect effect on neighboring industries have been analyzed, the indirect costs of other ailments in medicine have yet to be fully established. This case explores the ramifications of the SARS-CoV-2 pandemic on what would otherwise have been routine prophylaxis of malaria in a traveler. Given the pandemic, the healthcare industry has had fundamental changes that have impacted access to healthcare, particularly in the outpatient setting.

8.
Science ; 251(4989): 85-7, 1991 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-1824728

RESUMO

The N-methyl-D-aspartate (NMDA) subtype of the glutamate receptor is an important mediator of several forms of neural and behavioral plasticity. The present studies examined whether NMDA receptors might be involved in the development of opiate tolerance and dependence, two examples of behavioral plasticity. The noncompetitive NMDA receptor antagonist MK-801 attenuated the development of tolerance to the analgesic effect of morphine without affecting acute morphine analgesia. In addition, MK-801 attenuated the development of morphine dependence as assessed by naloxone-precipitated withdrawal. These results suggest that NMDA receptors may be important in the development of opiate tolerance and dependence.


Assuntos
Analgesia , Maleato de Dizocilpina/farmacologia , Morfina , Receptores de N-Metil-D-Aspartato/fisiologia , Transtornos Relacionados ao Uso de Substâncias , Animais , Comportamento Animal/efeitos dos fármacos , Tolerância a Medicamentos , Masculino , Naloxona/farmacologia , Medição da Dor , Ratos , Ratos Endogâmicos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores
9.
Science ; 210(4475): 1247-9, 1980 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-6254152

RESUMO

alpha-Melanocyte-stimulating hormone (alpha-MSH), a modified fragment of adrenocorticotropic hormone, derives from the same biosynthetic route as beta-endorphin and is stored by the same arcuate neurons. Microinjection of alpha-melanocyte-stimulating hormone and several related peptides into the periaqueductal gray matter significantly reduced responsiveness to pain and had a behavioral profile similar to that produced by beta-endorphin.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Encéfalo/efeitos dos fármacos , Endorfinas/farmacologia , Hormônios Estimuladores de Melanócitos/farmacologia , Dor/fisiopatologia , Hormônios Adeno-Hipofisários/metabolismo , Precursores de Proteínas/farmacologia , Analgesia , Animais , Aqueduto do Mesencéfalo , Masculino , Pró-Opiomelanocortina , Ratos
10.
Science ; 191(4230): 961-2, 1976 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-1251210

RESUMO

Analgesia produced by focal electrical stimulation of the brain is partially reversed by the narcotic antagonist naloxone. The absence of complete reversal does not appear to be caused by inadequate doses of naloxone since doses higher than 1 milligram per kilogram of body weight did not increase the antagonism. It is suggested that stimulation-produced analgesia may result, at least in part, from release of an endogenous, narcotic-like substance, such as that recently reported by other investigators.


Assuntos
Analgesia , Encéfalo/efeitos dos fármacos , Naloxona/farmacologia , Dor/fisiopatologia , Animais , Relação Dose-Resposta a Droga , Estimulação Elétrica , Masculino , Ratos
11.
Science ; 227(4685): 424-6, 1985 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-3155575

RESUMO

beta-Endorphin in the intermediate lobe of the pituitary gland is posttranslationally modified to produce opioid inactive peptides. Whether these are metabolites or biologically relevant products has not been known. It was found that repeated stress induces increased biosynthesis and release of beta-endorphin-like substances from the intermediate lobe of rats and that opioid-inactive N-acetylated beta-endorphin-(1-31) is selectively made and liberated. The possible role of this nonopioid product and the selective release of peptide forms are discussed.


Assuntos
Endorfinas/biossíntese , Hipófise/metabolismo , Estresse Fisiológico/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Endorfinas/sangue , Meia-Vida , Cinética , Hormônios Estimuladores de Melanócitos/biossíntese , Hormônios Estimuladores de Melanócitos/sangue , Ratos , beta-Endorfina
12.
Science ; 201(4354): 463-5, 1978 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-663668

RESUMO

Enkephalin-like activity has been measured in the ventricular cerebrospinal fluid of patients with intractable pain. Electrical stimulation of periventricular brain sites resulted in significant decrease in persistent pain in these subjects. This analgesia, which was blocked by naloxone in 80% of the cases, was accompanied by a significant rise in ventricular enkephalin-like activity, as measured by two different methods. The results present evidence of in vivo release of enkephalin-like material in humans and suggest that stimulation analgesia may be partially due to this release.


Assuntos
Encéfalo/fisiopatologia , Endorfinas/líquido cefalorraquidiano , Encefalinas/líquido cefalorraquidiano , Dor/líquido cefalorraquidiano , Aqueduto do Mesencéfalo , Estimulação Elétrica , Feminino , Humanos , Masculino , Dor/fisiopatologia , Manejo da Dor
13.
Science ; 201(4350): 73-6, 1978 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-351804

RESUMO

Endogenous opiate-like peptides (endorphins) are putative neuroregulators located throughout the mammalian brainstem. There is some evidence for their role in pain, stress, and affect. We report that the opiate antagonist, naloxone, alters some schizophrenic symptoms. In a double-blind, cross-over study, naloxone produced decreases in auditory hallucinations in some schizophrenic patients. This finding supports the hypothesis that the endorphins may play a roll in modulating hallucinations in a highly selected subgroup of chronically hallucinating schizophrenic patients.


Assuntos
Alucinações/tratamento farmacológico , Naloxona/uso terapêutico , Esquizofrenia/tratamento farmacológico , Adulto , Doença Crônica , Ensaios Clínicos como Assunto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Endorfinas/fisiologia , Humanos , Masculino , Naloxona/administração & dosagem , Esquizofrenia/fisiopatologia , Esquizofrenia Paranoide/tratamento farmacológico , Fatores de Tempo
14.
Science ; 218(4577): 1134-6, 1982 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-6128790

RESUMO

A study of the anatomical distribution of the endogenous opioid dynorphin in rat brain showed that the peptide is localized in a widespread system with multiple cell groups and projections. This network is revealed by the use of multiple antiserums against dynorphin and can be distinguished from the system containing methionine-enkephalin and leucine-enkephalin, which is mapped by the use of antiserums against the enkephalins and biosynthetically related peptides in the adrenal. It thus appears that the brain contains at least three separate opioid neuronal networks: an enkephalin family with components similar to those found in the adrenal, a beta-endorphin family, and a dynorphin family.


Assuntos
Encéfalo/fisiologia , Endorfinas/fisiologia , Encefalinas/fisiologia , Animais , Mapeamento Encefálico , Dinorfinas , Técnicas Imunológicas , Ratos
15.
Science ; 218(4577): 1136-8, 1982 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-6128791

RESUMO

Intracerebroventricular administration of dynorphin produced potent and long-lasting effects on motor function and the electroencephalogram in rats. In addition, local iontophoretic or pressure ejection of dynorphin consistently inhibited hippocampal unit activity. None of these effects were significantly affected by naloxone even at high doses. Moreover, a fragment of dynorphin that failed to displace any of a number of tritiated narcotics from rat brain homogenates produced similar effects on these physiological measures in vivo. On the basis of a variety of criteria for "opiate action," the results suggest that a second biologically active site within the dynorphin sequence is capable of quite potent but nonopiate effects.


Assuntos
Endorfinas/fisiologia , Hipocampo/fisiologia , Dor/fisiopatologia , Potenciais de Ação , Sequência de Aminoácidos , Animais , Dinorfinas , Masculino , Ratos , Relação Estrutura-Atividade
16.
Science ; 174(4016): 1351-4, 1971 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-5167502

RESUMO

Stimulation at several mesencephalic and diencephalic sites abolished responsiveness to intense pain in rats while leaving responsiveness to other sensory modes relatively unaffected. The peripheral field of analgesia was usually restricted to one-half or to one quadrant of the body, and painful stimuli applied outside this field elicited a normal reaction. Analgesia outlasted stimulation by up to 5 minutes. Most electrode placements that produced analgesia also supported self-stimulation. One placement supported self-stimulation only in the presence of pain.


Assuntos
Analgesia , Diencéfalo/fisiologia , Estimulação Elétrica , Mesencéfalo/fisiologia , Agressão , Animais , Comportamento Animal , Mapeamento Encefálico , Tronco Encefálico/fisiologia , Eletrodos Implantados , Reação de Fuga , Comportamento Alimentar , Humanos , Masculino , Ratos , Autoestimulação , Tegmento Mesencefálico , Tálamo , Fatores de Tempo
17.
Science ; 200(4344): 964-73, 1978 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-25486

RESUMO

There is compelling evidence that behavioral events after neurochemical function and that altered neurochemical function can change behavior. Such processes have been related both to neurotransmitters and to neuromodulators, together termed neuroregulators. Available research tools and theoretical constructs have begun to permit studies of certain types of behavior, primarily those related to emotional states and drives. This work is changing long-held concepts about severe mental disorders and the treatment of them.


Assuntos
Comportamento/fisiologia , Fenômenos Fisiológicos do Sistema Nervoso , Animais , Comunicação Celular , Depressão/fisiopatologia , Endorfinas/fisiologia , Encefalinas/fisiologia , Hormônios/fisiologia , Humanos , Transtornos Mentais/fisiopatologia , Neurônios/fisiologia , Neurotransmissores/fisiologia , Esquizofrenia/fisiopatologia , Sinapses/fisiologia
18.
Science ; 216(4541): 85-7, 1982 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-6121376

RESUMO

The opioid peptide dynorphin is widely distributed in neuronal tissue of rats. By immunocytochemical methods, it was shown previously that dynorphin-like immunoreactivity is present in the posterior pituitary and the cells of the hypothalamic neurosecretory magnocellular nuclei which also are responsible for the synthesis of oxytocin, vasopressin, and their neurophysins. By using an affinity-purified antiserum to the non-enkephalin part of the dynorphin molecule it has now been demonstrated that dynorphin and vasopressin occur in the same hypothalamic cells of rats, whereas dynorphin and oxytocin occur in separate cells. Homozygous Brattleboro rats (deficient in vasopressin) have magnocellular neurons that contain dynorphin separate from oxytocin. Thus dynorphin and vasopressin, although they occur in the same cells, appear to be under separate genetic control and presumably arise from different precursors.


Assuntos
Arginina Vasopressina/metabolismo , Endorfinas/metabolismo , Hipotálamo/metabolismo , Animais , Dinorfinas , Encefalina Leucina , Encefalinas/metabolismo , Hipotálamo/citologia , Técnicas Imunológicas , Masculino , Ratos
19.
Transl Psychiatry ; 9(1): 218, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31488811

RESUMO

Polyamines have fundamental roles in brain homeostasis as key modulators of cellular excitability. Several studies have suggested alterations in polyamine metabolism in stress related disorders, suicide, depression, and neurodegeneration, making the pharmacological modulation of polyamines a highly appealing therapeutic strategy. Polyamines are small aliphatic molecules that can modulate cationic channels involved in neuronal excitability. Previous indirect evidence has suggested that polyamines can modulate anionic GABAA receptors (GABAARs), which mediate inhibitory signaling and provide a direct route to reduce hyperexcitability. Here, we attempted to characterize the effect that spermine, the polyamine with the strongest reported effect on GABAARs, has on human postmortem native GABAARs. We microtransplanted human synaptic membranes from the dorsolateral prefrontal cortex of four cases with no history of mental or neurological disorders, and directly recorded spermine effects on ionic GABAARs responses on microtransplanted oocytes. We show that in human synapses, inhibition of GABAARs by spermine was better explained by alkalization of the extracellular solution. Additionally, spermine had no effect on the potentiation of GABA-currents by diazepam, indicating that even if diazepam binding is enhanced by spermine, it does not translate to changes in functional activity. Our results clearly demonstrate that while extracellular spermine does not have direct effects on human native synaptic GABAARs, spermine-mediated shifts of pH inhibit GABAARs. Potential spermine-mediated increase of pH in synapses in vivo may therefore participate in increased neuronal activity observed during physiological and pathological states, and during metabolic alterations that increase the release of spermine to the extracellular milieu.


Assuntos
Córtex Pré-Frontal/efeitos dos fármacos , Receptores de GABA-A/metabolismo , Espermina/farmacologia , Sinapses/efeitos dos fármacos , Membranas Sinápticas/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Córtex Pré-Frontal/metabolismo , Sinapses/metabolismo , Membranas Sinápticas/metabolismo
20.
Neuron ; 11(5): 903-13, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8240812

RESUMO

We have isolated a rat cDNA clone that displays 75% amino acid homology with the mouse delta and rat kappa opioid receptors. The cDNA (designated pRMuR-12) encodes a protein of 398 amino acids comprising, in part, seven hydrophobic domains similar to those described for other G protein-linked receptors. Data from binding assays conducted with COS-1 cells transiently transfected with a CMV mammalian expression vector containing the full coding region of pRMuR-12 demonstrated mu receptor selectivity. In situ hybridization mRNA analysis revealed an mRNA distribution in rat brain that corresponds well to the distribution of binding sites labeled with mu-selective ligands. Based upon these observations, we conclude that pRMuR-12 encodes a mu opioid receptor.


Assuntos
Clonagem Molecular , Receptores Opioides mu/genética , Receptores Opioides mu/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Northern Blotting , Southern Blotting , Linhagem Celular Transformada , DNA/genética , DNA Complementar/genética , Masculino , Dados de Sequência Molecular , Sondas de Oligonucleotídeos/genética , Conformação Proteica , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Transfecção
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