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1.
J Am Acad Orthop Surg ; 32(9): 410-416, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38422496

RESUMO

BACKGROUND: Supracondylar humerus fractures (SCHFs) are the most common elbow fracture in the pediatric population. In the case of displaced fractures, closed reduction and percutaneous Kirschner wire pinning (CRPP) is commonly performed. Infection rates are between 0 and 7%; however, retrospective studies have shown no benefit of preoperative antibiotics. There continues to be notable variability in antibiotic usage based on surgeon preference and local institutional policy. We conducted a double-blinded, randomized controlled trial to evaluate whether antibiotic prophylaxis reduces the risk of infection in pediatric SCHF patients treated with CRPP. METHODS: Pediatric patients with displaced SCHF who presented to a pediatric hospital were enrolled and randomized into two groups. Group I received one dose of prophylactic antibiotics (25 mg/kg cefazolin IV up to 1g or clindamycin 10 mg/kg up to 600 mg/kg IV in the case of cefazolin allergy). Group II received placebo (10-mL prefilled syringe of normal saline). All patients underwent CRPP and casting followed by pin removal 3 to 6 weeks after the initial procedure. The presence of pin-site infection, erythema, drainage, septic arthritis, and osteomyelitis was recorded. RESULTS: One hundred sixty patients were enrolled in the study. Eighty-two patients were randomized to receive antibiotics, and 78 patients were randomized to placebo. No difference was seen in the rate of infection between the treatment groups (1.2% in the antibiotic group versus 1.3% in the placebo group; P = 1.00). Presence of purulent drainage (0.0% versus 1.3%; P = 0.49), septic arthritis (0.0% versus 0.0%; P = 1.00), and osteomyelitis (1.2% versus 0.0%; P = 1.00) was similar in both groups. No difference in the need for additional antibiotics (1.2% versus 1.3%; P = 1.00) or additional surgery (1.2% versus 0.0%; P = 1.00) was found between groups. DISCUSSION: The use of antibiotic prophylaxis did not affect the risk of infection in pediatric patients who underwent CRPP for displaced SCHF. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: NCT03261830. LEVEL OF EVIDENCE: Therapeutic Level I.


Assuntos
Artrite Infecciosa , Fraturas do Úmero , Osteomielite , Criança , Humanos , Antibacterianos/uso terapêutico , Antibioticoprofilaxia , Artrite Infecciosa/etiologia , Pinos Ortopédicos/efeitos adversos , Cefazolina/uso terapêutico , Fraturas do Úmero/cirurgia , Osteomielite/etiologia , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento , Método Duplo-Cego
2.
PLoS One ; 8(2): e56501, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23431380

RESUMO

Systemic administration of a Synthetic Proteasome Inhibitor (PSI) in rats has been described as able to provide a model of Parkinson's disease (PD), characterized by behavioral and biochemical modifications, including loss of dopaminergic neurons in the substantia nigra (SN), as assessed by post-mortem studies. With the present study we aimed to assess in-vivo by Magnetic Resonance (MR) possible morphological and metabolic changes in the nigro-striatal pathway of PSI-treated rats. 10 animals were subcutaneously injected with PSI 6.0 mg/kg dissolved in DMSO 100%. Injections were made thrice weekly over the course of two weeks. 5 more animals injected with DMSO 100% with the same protocol served as controls. The animals underwent MR sessions before and at four weeks after the end of treatment with either PSI or vehicle. MR Imaging was performed to measure SN volume and Proton MR Spectroscopy ((1)H-MRS) was performed to measure metabolites changes at the striatum. Animals were also assessed for motor function at baseline and at 4 and 6 weeks after treatment. Dopamine and dopamine metabolite levels were measured in the striata at 6 weeks after treatment. PSI-treated animals showed volumetric reduction of the SN (p<0.02) at 4 weeks after treatment as compared to baseline. Immunofluorescence analysis confirmed MRI changes in SN showing a reduction of tyrosine hydroxylase expression as compared to neuron-specific enolase expression. A reduction of N-acetyl-aspartate/total creatine ratio (p = 0.05) and an increase of glutamate-glutamine-γ amminobutirrate/total creatine were found at spectroscopy (p = 0.03). At 6 weeks after treatment, PSI-treated rats also showed motor dysfunction compared to baseline (p = 0.02), accompanied by dopamine level reduction in the striatum (p = 0.02). Treatment with PSI produced morphological and metabolic modifications of the nigro-striatal pathway, accompanied by motor dysfunction. MR demonstrated to be a powerful mean to assess in-vivo the nigro-striatal pathway morphology and metabolism in the PSI-based PD animal model.


Assuntos
Oligopeptídeos/farmacologia , Transtornos Parkinsonianos/patologia , Inibidores de Proteassoma/farmacologia , Substância Negra/patologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Modelos Animais de Doenças , Dopamina/metabolismo , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Atividade Motora/efeitos dos fármacos , Neuroimagem , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/metabolismo , Ratos , Ratos Sprague-Dawley , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo
3.
J Neurosci ; 31(44): 15742-50, 2011 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-22049417

RESUMO

Serotonin (5-HT)-selective reuptake inhibitors (SSRIs) are widely administered for the treatment of depression, anxiety, and other neuropsychiatric disorders, but response rates are low, and side effects often lead to discontinuation. Side effect profiles suggest that SSRIs inhibit dopaminergic activity, but mechanistic insight remains scarce. Here we show that in mice, chronic 5-HT transporter (5-HTT) blockade during adulthood but not during development impairs basal ganglia-dependent behaviors in a dose-dependent and reversible fashion. Furthermore, chronic 5-HTT blockade reduces striatal dopamine (DA) content and metabolism. A causal relationship between reduced DA signaling and impaired basal ganglia-dependent behavior is indicated by the reversal of behavioral deficits through L-DOPA administration. Our data suggest that augmentation of DA signaling would reduce side effects and increase efficacies of SSRI-based therapy.


Assuntos
Gânglios da Base/efeitos dos fármacos , Dopamina/metabolismo , Fluoxetina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Transdução de Sinais/efeitos dos fármacos , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Fatores Etários , Animais , Animais Recém-Nascidos , Gânglios da Base/patologia , Gânglios da Base/fisiopatologia , Contagem de Células , Cromatografia Líquida de Alta Pressão/métodos , Dopaminérgicos/farmacologia , Dopaminérgicos/uso terapêutico , Relação Dose-Resposta a Droga , Esquema de Medicação , Interações Medicamentosas , Comportamento Exploratório/efeitos dos fármacos , Fluoxetina/uso terapêutico , Ácido Homovanílico/metabolismo , Levodopa/farmacologia , Levodopa/uso terapêutico , Masculino , Camundongos , Camundongos Transgênicos , Transtornos dos Movimentos/tratamento farmacológico , Transtornos dos Movimentos/genética , Transtornos dos Movimentos/patologia , Desempenho Psicomotor/efeitos dos fármacos , Distribuição Aleatória , Teste de Desempenho do Rota-Rod , Serotonina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/deficiência , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Transdução de Sinais/fisiologia , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo , Substância Negra/patologia , Área Tegmentar Ventral/citologia , Área Tegmentar Ventral/efeitos dos fármacos
4.
CNS Neurosci Ther ; 16(3): 179-94, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20557570

RESUMO

The interaction between serotonin (5-HT) and dopamine (DA)-containing neurons in the brain is a research topic that has raised the interest of many scientists working in the field of neuroscience since the first demonstration of the presence of monoamine-containing neurons in the mid 1960. The bulk of neuroanatomical data available clearly indicate that DA-containing neurons in the brain receive a prominent innervation from serotonin (5-hydroxytryptamine, 5-HT) originating in the raphe nuclei of the brainstem. Compelling electrophysiological and neurochemical data show that 5-HT can exert complex effects on the activity of midbrain DA neurons mediated by its various receptor subtypes. The main control seems to be inhibitory, this effect being more marked in the mesocorticolimbic DA system as compared to the DA nigrostriatal system. In spite of a direct effect of 5-HT by its receptors located on DA cells, 5-HT can modulate their activity indirectly, modifying gamma-aminobutyric (GABA)-ergic and glutamatergic input to the ventral tegmental area (VTA) and substantia nigra pars compacta (SNc). Although 5-HT/DA interaction in the brain has been extensively studied, much work remains to be done to clarify this issue. The recent development of subtype-selective ligands for 5-HT receptors will not only allow a detailed understanding of this interaction but also will lead to the development of new treatment strategies, appropriate for those neuropsychiatric disorders in which an alteration of the 5-HT/DA balance is supposed.


Assuntos
Doenças do Sistema Nervoso Central/metabolismo , Dopamina/metabolismo , Serotonina/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Doenças do Sistema Nervoso Central/patologia , Humanos
5.
CNS Neurosci Ther ; 16(3): 127-36, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20345972

RESUMO

Nicotine, the main psychoactive ingredient in tobacco, stimulates dopamine (DA) function, increasing DA neuronal activity and DA release. DA is involved in both motor control and in the rewarding and reinforcing effects of nicotine; however, the complete understanding of its molecular mechanisms is yet to be attained. Substantial evidence indicates that the reinforcing properties of drugs of abuse, including nicotine, can be affected by the nitric oxide (NO) system, which may act by modulating central dopaminergic function. In this study, using single cell recordings in vivo coupled with microiontophoresis and microdialysis in freely moving animals, the role of NO signaling on the hyperactivation elicited by nicotine of the nigrostriatal system was investigated in rats. Nicotine induced a dose-dependent increase of the firing activity of the substantia nigra pars compacta (SNc) DA neurons and DA and 3,4-dihydroxyphenylacetic acid (DOPAC) release in the striatum. Pharmacological manipulation of the NO system did not produce any change under basal condition in terms of neuronal discharge and DA release. In contrast, pretreatments with two NO synthase (NOS) inhibitors, N-omega-nitro-l-arginine methyl ester (l-NAME) and 7-nitroindazole (7-NI) were both capable of blocking the nicotine-induced increase of SNc DA neuron activity and DA striatal levels. The effects of nicotine in l-NAME and 7-NI-pretreated rats were partially restored when rats were pretreated with the NO donor molsidomine. These results further support the evidence of an important role played by NO on modulation of dopaminergic function and drug addiction, thus revealing new pharmacological possibilities in the treatment of nicotine dependence and other DA dysfunctions.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Dopamina/metabolismo , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Óxido Nítrico/metabolismo , Substância Negra/efeitos dos fármacos , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Análise de Variância , Animais , Arginina/farmacologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Inibidores Enzimáticos/farmacologia , Indazóis/farmacologia , Masculino , Microdiálise/métodos , NG-Nitroarginina Metil Éster/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley , Substância Negra/citologia , Fatores de Tempo
6.
J Biomed Sci ; 17: 14, 2010 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-20178616

RESUMO

BACKGROUND: Both hypoxia and hyperoxia, deregulating the oxidative balance, may play a role in the pathology of neurodegenerative disorders underlain by cerebral ischemia. In the present study, quantitative proton magnetic resonance spectroscopy was used to evaluate regional metabolic alterations, following a 24-hour hypoxic or hyperoxic exposure on the background of ischemic brain insult, in two contrasting age-groups of rats: young--3 months old and aged--24 months old. METHODS: Cerebral ischemia was induced by ligation of the right common carotid artery. Concentrations of eight metabolites (alanine, choline-containing compounds, total creatine, gamma-aminobutyric acid, glutamate, lactate, myo-inositol and N-acetylaspartate) were quantified from extracts in three different brain regions (fronto-parietal and occipital cortices and the hippocampus) from both hemispheres. RESULTS: In the control normoxic condition, there were significant increases in lactate and myo-inositol concentrations in the hippocampus of the aged rats, compared with the respective values in the young ones. In the ischemia-hypoxia condition, the most prevalent changes in the brain metabolites were found in the hippocampal regions of both young and aged rats; but the effects were more evident in the aged animals. The ischemia-hyperoxia procedure caused less dedicated changes in the brain metabolites, which may reflect more limited tissue damage. CONCLUSIONS: We conclude that the hippocampus turns out to be particularly susceptible to hypoxia overlaid on cerebral ischemia and that old age further increases this susceptibility.


Assuntos
Isquemia Encefálica/metabolismo , Encéfalo/metabolismo , Hiperóxia/metabolismo , Hipóxia-Isquemia Encefálica/metabolismo , Envelhecimento/metabolismo , Animais , Animais Recém-Nascidos , Isquemia Encefálica/complicações , Feminino , Hiperóxia/complicações , Espectroscopia de Ressonância Magnética , Masculino , Prótons , Ratos , Ratos Sprague-Dawley
7.
J Neurosci ; 29(25): 8156-65, 2009 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-19553455

RESUMO

The impact of serotonergic neurotransmission on brain dopaminergic pathways has substantial relevance to many neuropsychiatric disorders. A particularly prominent role has been ascribed to the inhibitory effects of serotonin 2C receptor (5-HT(2C)R) activation on physiology and behavior mediated by the mesolimbic dopaminergic pathway, particularly in the terminal region of the nucleus accumbens. The influence of this receptor subtype on functions mediated by the nigrostriatal dopaminergic pathway is less clear. Here we report that a null mutation eliminating expression of 5-HT(2C)Rs produces marked alterations in the activity and functional output of this pathway. 5-HT(2C)R mutant mice displayed increased activity of substantia nigra pars compacta (SNc) dopaminergic neurons, elevated baseline extracellular dopamine concentrations in the dorsal striatum (DSt), alterations in grooming behavior, and enhanced sensitivity to the stereotypic behavioral effects of d-amphetamine and GBR 12909. These psychostimulant responses occurred in the absence of phenotypic differences in drug-induced extracellular dopamine concentration, suggesting a phenotypic alteration in behavioral responses to released dopamine. This was further suggested by enhanced behavioral responses of mutant mice to the D(1) receptor agonist SKF 81297. Differences in DSt D(1) or D(2) receptor expression were not found, nor were differences in medium spiny neuron firing patterns or intrinsic membrane properties following dopamine stimulation. We conclude that 5-HT(2C)Rs regulate nigrostriatal dopaminergic activity and function both at SNc dopaminergic neurons and at a locus downstream of the DSt.


Assuntos
Comportamento Animal/fisiologia , Corpo Estriado/fisiologia , Dopamina/metabolismo , Vias Neurais/fisiologia , Neurônios/fisiologia , Receptor 5-HT2C de Serotonina/fisiologia , Substância Negra/fisiologia , Anfetamina/administração & dosagem , Anfetamina/farmacologia , Animais , Autorradiografia , Comportamento Animal/efeitos dos fármacos , Benzazepinas/administração & dosagem , Benzazepinas/farmacologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Dopaminérgicos/administração & dosagem , Dopaminérgicos/farmacologia , Agonistas de Dopamina/administração & dosagem , Agonistas de Dopamina/farmacologia , Inibidores da Captação de Dopamina/administração & dosagem , Inibidores da Captação de Dopamina/farmacologia , Eletrofisiologia , Asseio Animal/fisiologia , Locomoção/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Piperazinas/administração & dosagem , Piperazinas/farmacologia , Receptor 5-HT2C de Serotonina/deficiência , Receptor 5-HT2C de Serotonina/genética , Comportamento Estereotipado/fisiologia , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo
8.
Ann N Y Acad Sci ; 1155: 309-15, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19250222

RESUMO

The present study was undertaken to explore the involvement of nitric oxide (NO) in the 6-hydroxydopamine (6-OHDA) experimental model of Parkinson's disease (PD) in rats. The effect of pharmacological manipulation of the NO system was evaluated on striatal dopamine (DA) level decrease produced by the toxin. 7-nitroindazole (7-NI, 50 mg/kg i.p.; n= 5) pretreatment significantly restored the striatal DA contents. Conversely, 40 mg/kg i.p. of molsidomine (MOL, n= 5), an NO donor, significantly worsened the neurodegeneration (n= 5) and completely counteracted the neuroprotective effect of 7-NI (n= 5). Thus, a crucial role for NO in 6-OHDA induced neurodegeneration is suggested together with a protective benefit for inhibitors of NOS in the treatment of PD.


Assuntos
Corpo Estriado/patologia , Óxido Nítrico/fisiologia , Substância Negra/patologia , Animais , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Indazóis/farmacologia , Masculino , Molsidomina/farmacologia , Doadores de Óxido Nítrico , Oxidopamina/metabolismo , Doença de Parkinson/metabolismo , Ratos , Ratos Sprague-Dawley , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo
9.
Ann N Y Acad Sci ; 1155: 316-23, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19250223

RESUMO

6-Hydroxydopamine (6-OHDA) is a neurotoxic compound commonly used to induce dopamine (DA) depletion in the nigrostriatal system, mimicking Parkinson's disease (PD) in animals. The aim of the present study was to evaluate the 7-day effect of unilateral nigral lesion on rat brain monoamine neurochemistry. Five brain regions were examined: the brain stem, cerebellum, hippocampus, striatum, and cortex. 6-OHDA-unilateral lesion dramatically modified DA, serotonin (5-HT) and their metabolites contents in both sides of the different brain nuclei. Furthermore, unilateral 6-OHDA lesion reduced DA and 5-HT contents and produced a robust inversion of their turnover in the nonlesioned side compared to sham-operated rats. These data suggest that 6-OHDA unilateral nigral lesion produces bilateral monoamine level modifications, and this piece of evidence should be taken into account when one interprets data from animal models of unilateral PD.


Assuntos
Monoaminas Biogênicas/metabolismo , Encéfalo/metabolismo , Substância Negra/patologia , Animais , Encéfalo/patologia , Cromatografia Líquida de Alta Pressão , Masculino , Ratos , Ratos Sprague-Dawley
10.
J Neural Transm Suppl ; (73): 173-82, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20411777

RESUMO

Nitric oxide (NO) plays an important role in the integration of information processed by the basal ganglia nuclei. Accordingly, considerable evidence has emerged indicating a role for NO in pathophysiological conditions such as Parkinson's disease (PD) and other neurodegenerative disorders. Despite these recent advances, the nitrergic modulation of the dopamine (DA) nigrostriatal system is still unclear. In order to fill this gap, in this study we used in vivo electrophysiology and ex vivo neurochemical analysis to further investigate the effect of NO signaling in rat substantia nigra pars compacta (SNc) and the striatum. Acute and subchronic (4 days) pharmacological manipulation of the NO system using 7-nitroindazole (7-NI, 50 mg kg(-1) i.p.) and molsidomine (MOL, 40 mg kg(-1) i.p.) treatment caused significant changes in both DA SNc neurons electrophysiological properties and striatal DA and 3,4-dihydroxyphenylacetic acid (DOPAC) levels. It is worth noting that acute inhibition of NO production decreased DA nigrostriatal neurotransmission while its subchronic inhibition was instead excitatory. Thus, a crucial role for NO in the modulation of nigrostriatal DA function is suggested together with a potential role for inhibitors of NO sythase in the treatment of PD.


Assuntos
Corpo Estriado , Inibidores Enzimáticos/administração & dosagem , Indazóis/administração & dosagem , Molsidomina/administração & dosagem , Doadores de Óxido Nítrico/administração & dosagem , Substância Negra , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Potenciais de Ação/efeitos dos fármacos , Animais , Cromatografia Líquida de Alta Pressão/métodos , Corpo Estriado/citologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Dopamina/metabolismo , Esquema de Medicação , Masculino , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Ratos , Ratos Sprague-Dawley , Substância Negra/citologia , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo
11.
J Neural Transm Suppl ; (73): 223-43, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20411781

RESUMO

Parkinson's disease (PD) is a progressive neurodegenerative disorder that is primarily characterized by the degeneration of dopamine (DA) neurons in the nigrostriatal system, which in turn produces profound neurochemical changes within the basal ganglia, representing the neural substrate for parkinsonian motor symptoms. The pathogenesis of the disease is still not completely understood, but environmental and genetic factors are thought to play important roles. Research into the pathogenesis and the development of new therapeutic intervention strategies that will slow or stop the progression of the disease in human has rapidly advanced by the use of neurotoxins that specifically target DA neurons. Over the years, a broad variety of experimental models of the disease has been developed and applied in diverse animal species. The two most common toxin models used employ 6-hydroxydopamine (6-OHDA) and the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine/1-methyl-4-phenilpyridinium ion (MPTP/MPP+), either given systemically or locally applied into the nigrostriatal pathway, to resemble PD features in animals. Both neurotoxins selectively and rapidly destroy catecolaminergic neurons, although with different mechanisms. Since in vivo microdialysis coupled to high-performance liquid chromatography is an established technique for studying physiological, pharmacological, and pathological changes of a wide range of low molecular weight substances in the brain extracellular fluid, here we review the most prominent animal and human data obtained by the use of this technique in PD research.


Assuntos
Pesquisa Biomédica/métodos , Modelos Animais de Doenças , Microdiálise/métodos , Doença de Parkinson , Animais , Dopamina/metabolismo , Humanos , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia
12.
J Neural Transm Suppl ; (73): 333-41, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20411791

RESUMO

There is extensive evidence that oxidative damage of dopamine (DA)-containing neurons in the substantia nigra pars compacta (SNc) may contribute to the pathogenesis of Parkinson's disease (PD). We evaluated the potential neuroprotective effect of diets enriched with wild-type Red Setter (RS) tomato or transgenic High Carotene (HC) tomato, rich in beta-carotene, obtained by the activation of lycopene beta-cyclase (tlcy-b), in an animal model of PD. Male Fischer 344 rats were fed for 14 days with standard Altromin diet, 5% RS- or 5% HC-enriched diet. Seven days after the beginning of this diet regimen, the rats were lesioned by 6-hydroxydopamine (6-OHDA) injected into the left SNc. After further 7 days, the rats were sacrificed, and DA and 3,4-dihydroxyphenylacetic acid (DOPAC) levels in both the left (ipsilateral) and the right (contralateral) striata were measured. Striatal DA levels were reduced by 86.5 +/- 5.0% in control, 86.2 +/- 5.0% in HC-, and 56.0 +/- 9.0% in RS-fed group. Striatal DOPAC was decreased by 85.6 +/- 5.0% in controls, 83.0 +/- 6.0% in HC-, and 58.9 +/- 10.0% in RS-fed group. Blood was obtained from the rats on day 14 and the plasma level of licopene and beta-carotene was measured by liquid chromatography-atmospheric pressure chemical ionization-mass spectrometry (LC-APCI-MS) for the determination of lycopene and beta-carotene levels. The plasma level of lycopene was 4.7 +/- 0.2 ng/ml in 5% RS-fed rats, while it was undetectable (< 2.5 ng ml(-1)) in control and HC-fed rats. The efficacy of RS diet to preserve striatal dopaminergic innervation can be attributed to the ability of lycopene to prevent the degeneration of DA-containing neurons in the SNc.


Assuntos
Dopamina/metabolismo , Degeneração Neural/patologia , Degeneração Neural/prevenção & controle , Solanum lycopersicum/química , Substância Negra/patologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Carotenoides/administração & dosagem , Carotenoides/biossíntese , Modelos Animais de Doenças , Lateralidade Funcional , Liases Intramoleculares/sangue , Liases Intramoleculares/genética , Solanum lycopersicum/genética , Masculino , Degeneração Neural/sangue , Degeneração Neural/etiologia , Oxidopamina/toxicidade , Doença de Parkinson/complicações , Doença de Parkinson/etiologia , Plantas Geneticamente Modificadas , Ratos , Ratos Endogâmicos F344
14.
Prog Brain Res ; 172: 3-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18772025

RESUMO

Central serotonergic and dopaminergic systems play a critical role in the regulation of normal and abnormal behaviours. Moreover, recent evidence suggests that the dysfunction of dopamine (DA) and serotonin (5-hydroxytriptamine, 5-HT) neurotransmission might underlie the pathophysiology of neuropsychiatric disorders, including depression, schizophrenia, attention deficit hyperactivity disorders, drug abuse, Gilles de la Tourette's syndrome and Parkinson's disease.


Assuntos
Dopamina/metabolismo , Serotonina/metabolismo , Comportamento/fisiologia , Encéfalo/anatomia & histologia , Encéfalo/metabolismo , Humanos , Transtornos Mentais/fisiopatologia , Transmissão Sináptica/fisiologia
15.
Prog Brain Res ; 172: 7-44, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18772026

RESUMO

In this review, the functional interactions between serotonin (5-HT) and dopamine (DA) neuronal systems are discussed with the focus on microdialysis studies in the rodent brain (mainly rats). 5-HT by itself is involved both directly and indirectly via actions on complex neuronal circuitry, in the regulation of DA release through multiple 5-HT receptors, playing a critical role in the development of normal and abnormal behaviours. Recent evidence suggests that dysfunction of dopaminergic and serotoninergic neurotransmitter systems contributes to various disorders including depression, schizophrenia, Parkinson's disease and drug abuse. Here we summarize recent neurochemical works that have extensively explored the role of 5-HT receptors in the control of DA central systems in both basal and drug-induced conditions, using in vivo microdialytic techniques. Several 5-HT receptor subtypes, including the 5-HT(1A), 5-HT(1B), 5-HT(2A), 5-HT(3) and 5-HT(4) receptors, act to facilitate DA release, while the 5-HT(2C) receptor mediates an inhibitory effect of 5-HT on DA release. Taken together, neurochemical approaches using microdialysis can not only contribute to clarification of the physiological role of the serotonergic neuronal systems but may also be a powerful pharmacological approach for the development of therapeutic strategies to the treatment of depression, schizophrenia, Parkinson's disease and drug abuse.


Assuntos
Dopamina/metabolismo , Microdiálise/métodos , Serotonina/metabolismo , Animais , Corpo Estriado/anatomia & histologia , Corpo Estriado/metabolismo , Agonistas de Dopamina/metabolismo , Antagonistas de Dopamina/metabolismo , Humanos , Drogas Ilícitas/metabolismo , Transtornos Mentais/fisiopatologia , Mesencéfalo/anatomia & histologia , Mesencéfalo/metabolismo , Microdiálise/instrumentação , Vias Neurais/anatomia & histologia , Vias Neurais/fisiologia , Receptores de Serotonina/classificação , Receptores de Serotonina/metabolismo , Antagonistas da Serotonina/metabolismo , Agonistas do Receptor de Serotonina/metabolismo , Substância Negra/anatomia & histologia , Substância Negra/metabolismo , Transmissão Sináptica/fisiologia
16.
Prog Brain Res ; 172: 45-71, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18772027

RESUMO

In this review, the most relevant data regarding serotonin (5-hydroxytryptamine, 5-HT)/dopamine (DA) interaction in the brain, as studied by both in vivo and in vitro electrophysiological methods, are reported and discussed. The bulk of neuroanatomical data available clearly indicate that DA-containing neurons in the brain receive a prominent innervation from 5-HT originating in the raphe nuclei of the brainstem. Furthermore, this modulation seems to be reciprocal; DA neurons innervate the raphe nuclei and exert a tonic excitatory effect on them. Compelling electrophysiological data show that 5-HT can exert complex effects on the electrical activity of midbrain DA neurons mediated by the various receptor subtypes. The main control seems to be inhibitory, this effect being more marked in the ventral tegmental area (VTA) as compared to the substantia nigra pars compacta (SNc). In spite of a direct effect of 5-HT by its receptors located on DA cells, 5-HT can modulate their activity indirectly, modifying gamma-amino-n-butyric acid (GABA)-ergic and glutamatergic input to the VTA and SNc. Although 5-HT/DA interaction in the brain has been extensively studied, much work remains to be done to clarify this issue. The recent development of subtype-selective ligands for 5-HT receptors will not only allow a detailed understanding of this interaction but also lead to development of new treatment strategies, appropriate for those neuropsychiatric disorders in which an alteration of the 5-HT/DA balance is supposed.


Assuntos
Encéfalo , Dopamina/metabolismo , Eletrofisiologia , Serotonina/metabolismo , Animais , Encéfalo/anatomia & histologia , Encéfalo/metabolismo , Agonistas de Dopamina/metabolismo , Antagonistas de Dopamina/metabolismo , Estimulação Elétrica , Vias Neurais/anatomia & histologia , Vias Neurais/fisiologia , Neurônios/citologia , Neurônios/fisiologia , Receptores de Serotonina/classificação , Receptores de Serotonina/metabolismo , Antagonistas da Serotonina/metabolismo , Agonistas do Receptor de Serotonina/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/metabolismo
17.
Prog Brain Res ; 172: 423-63, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18772045

RESUMO

Several recent studies have emphasized a crucial role for the interactions between serotonergic and dopaminergic systems in movement control and the pathophysiology of basal ganglia. These observations are supported by anatomical evidence demonstrating large serotonergic innervation of all the basal ganglia nuclei. In fact, serotonergic terminals have been reported to make synaptic contacts with both substantia nigra dopamine-containing neurons and their terminal areas such as the striatum, the globus pallidus and the subthalamus. These brain areas contain a high concentration of serotonin (5-HT), with the substantia nigra pars reticulata receiving the greatest input. In this chapter, the distribution of different 5-HT receptor subtypes in the basal ganglia nuclei will be described. Furthermore, evidence demonstrating the serotonergic control of basal ganglia activity will be reviewed and the contribution of the different 5-HT receptor subtypes examined. The new avenues that the increasing knowledge of 5-HT in motor control has opened for exploring the pathophysiology and pharmacology of Parkinson's disease and other movement disorders will be discussed. It is clear that these avenues will be fruitful, despite the disappointing results so far obtained by clinical studies with selective 5-HT ligands. Nevertheless, these studies have led to a great increase in the attention given to the neurotransmitters of the basal ganglia and their connections.


Assuntos
Gânglios da Base/metabolismo , Transtornos dos Movimentos/tratamento farmacológico , Transtornos dos Movimentos/metabolismo , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Serotoninérgicos/uso terapêutico , Serotonina/metabolismo , Animais , Antipsicóticos/uso terapêutico , Gânglios da Base/anatomia & histologia , Modelos Animais de Doenças , Dopamina/metabolismo , Humanos , Transtornos dos Movimentos/fisiopatologia , Vias Neurais/anatomia & histologia , Vias Neurais/fisiologia , Doença de Parkinson/fisiopatologia , Doença de Parkinson/psicologia , Isoformas de Proteínas/metabolismo , Receptores de Serotonina/metabolismo
19.
Eur J Pharmacol ; 573(1-3): 148-60, 2007 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-17689529

RESUMO

The present study describes the pharmacological profile of the putative antipsychotic drug Lu 35-138 ((+)-(S)-3-{1-[2-(1-acetyl-2,3-dihydro-1H-indol-3-yl)ethyl]-3,6-dihydro-2H-pyridin-4-yl}-6-chloro-1H-indole). The in vitro receptor profile of Lu 35-138 revealed high affinity (K(i)=5 nM) and competitive antagonism (K(b)=8 nM) at dopamine D(4) receptors combined with potent 5-HT uptake inhibition (IC(50)=3.2 nM) and moderate alpha(1)-adrenoceptor affinity (K(i)=45 nM). In vivo, Lu 35-138 selectively counteracted hyperlocomotion induced by d-amphetamine (0.5 mg/kg; ED(50)=4.0 mg/kg, s.c.) in rats and phencyclidine (PCP; 2.5 mg/kg; ED(50)=13 mg/kg, s.c.) in mice. Lu 35-138 was unable to affect hyperlocomotion induced by a high dose of d-amphetamine (2.0 mg/kg), which indicates a preferential action on limbic versus striatal structures. A similar limbic selectivity of Lu 35-138 was indicated in voltammetric measure of dopamine output in the core and shell subdivisions of the nucleus accumbens in rats. Furthermore, a relatively large dose of Lu 35-138 (18 mg/kg, s.c.) counteracted d-amphetamine-induced disruption of pre-pulse inhibition in rats and repeated administration of Lu 35-138 (0.31 or 1.25 mg/kg, p.o. once daily for 3 weeks) reduced the number of spontaneously active dopamine neurones in the ventral tegmental area, underlining its antipsychotic-like profile. Lu 35-138 failed to induce catalepsy in rats or dystonia in Cebus apella monkeys and did not deteriorate spatial memory in rats as assessed by water maze performance. Collectively, these results suggest that Lu 35-138 possesses antipsychotic activity combined with a low extrapyramidal and cognitive side effect liability.


Assuntos
Di-Hidropiridinas/farmacologia , Indóis/farmacologia , Atividade Motora/efeitos dos fármacos , Receptores de Dopamina D4/antagonistas & inibidores , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Antagonistas de Receptores Adrenérgicos alfa 1 , Animais , Animais não Endogâmicos , Benzodiazepinas/farmacologia , Cebus , Citalopram/farmacologia , Clozapina/farmacologia , Cognição/efeitos dos fármacos , Di-Hidropiridinas/química , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Feminino , Haloperidol/farmacologia , Haplorrinos , Humanos , Indóis/química , Masculino , Camundongos , Estrutura Molecular , Olanzapina , Piperazinas/química , Piperazinas/farmacologia , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Risperidona/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/química , Sulfonamidas/farmacologia
20.
Brain Res ; 1168: 90-6, 2007 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-17706944

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder which is mostly sporadic, although about 5-10% of the cases are inherited. About 15-20% of patients with familial ALS (FALS) carry mutations in the gene encoding the free radical scavenging enzyme Cu/Zn superoxide dismutase (SOD1). In this study, we explored the potential neuroprotective effects of antioxidant strategies based on either a tomato-enriched diet, or pyruvate administration, in an animal model of ALS. To that aim, transgenic mice expressing a mutant form of SOD1 [the gly(93) --> ala (G93A) substitution; G93A SOD1] were fed on either tomato-enriched food pellets or the Altromin diet in which milk serum and proteins substitute for soy and fish flours. In both cases, treatments were started at the 29th day of age. In a second set of experiments, G93A SOD1 mice were treated with pyruvate intraperitoneally (500 mg/kg, i.p; starting at the 70th day of age) and compared with control mice receiving i.p. saline injections. Our results indicate that neither the tomato-enriched diet nor pyruvate administration caused any significant effect on the overall survival time and disease onset in G93A SOD1 mice. Thus, despite the wealth of data indicating the relevant role of oxidative stress and defective energy homeostasis both in patients and animal models of ALS, antioxidant strategies based on tomato-enriched food or pyruvate seem to be not sufficient to promote a disease modifying effect in an animal model of ALS.


Assuntos
Idade de Início , Esclerose Lateral Amiotrófica/terapia , Antioxidantes/uso terapêutico , Alimentos Fortificados , Ácido Pirúvico/uso terapêutico , Solanum lycopersicum , Esclerose Lateral Amiotrófica/sangue , Esclerose Lateral Amiotrófica/mortalidade , Animais , Carotenoides/sangue , Modelos Animais de Doenças , Flavonoides/sangue , Humanos , Camundongos , Camundongos Transgênicos , Superóxido Dismutase/genética , Análise de Sobrevida
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