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1.
J Shoulder Elbow Surg ; 24(4): e83-90, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25457777

RESUMO

HYPOTHESIS: Because a 4-dimensional CT scan (4D CT) is able to provide a moving 3-dimensional (3D) image in real time in patients with snapping scapula syndrome, a 4D CT scan should be able to demonstrate bony impingement of the scapula on the posterior thorax. This study was performed to determine if 4D CT scans aid the clinician in defining the size and location of the scapular bone causing impingement in patients with snapping scapula syndrome. MATERIALS AND METHODS: Between October 2009 and August 2013, 12 patients (median age, 26.5 years; range 15-55 years) with snapping scapula syndrome were investigated with 4D CT. The images formed produced a dynamic volume-rendered reconstruction of the scapulothoracic joint that displayed its movements and any dynamic area of impingement of the scapula on surrounding bony structures. Asymmetry between symptomatic and asymptomatic scapulae was used to determine the radiologic cause of the patient's symptoms. After the failure of conservative management, 8 patients underwent surgery for their condition. RESULTS: Five patients demonstrated bony contact of the scapula on the posterior thoracic ribs. Four patients demonstrated no bony contact but close apposition of the scapula to the posterior thoracic ribs. Three patients demonstrated no bony impingement but abnormal movement of the second and third rib caused by a soft-tissue tethering structure. CONCLUSION: The 4D CT scan images defined pathology well in patients with snapping scapula syndrome and improved assessment of the amount and location of the scapular bone and soft tissue causing symptoms.


Assuntos
Tomografia Computadorizada Quadridimensional , Artropatias/diagnóstico por imagem , Escápula/diagnóstico por imagem , Escápula/cirurgia , Parede Torácica/diagnóstico por imagem , Adolescente , Adulto , Feminino , Humanos , Artropatias/cirurgia , Masculino , Pessoa de Meia-Idade , Movimento , Dor Musculoesquelética/cirurgia , Período Pré-Operatório , Estudos Retrospectivos , Costelas/diagnóstico por imagem , Síndrome , Adulto Jovem
2.
Skeletal Radiol ; 42(4): 473-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22933016

RESUMO

OBJECTIVES: To describe the plane of the sternoclavicular joint (SCJ) to aid planning of instrument orientation during invasive procedures. METHODS: Computed tomography (CT) images of 80 consecutive patients aged 25 to 40 years with appropriate chest imaging series were retrospectively reviewed. Patients with a previous median sternotomy, fused manubriosternal joint or fracture were excluded. The medial clavicle was found to vary greatly in its anatomy such that a representative morphology could not be described. The manubrium was found to be a more consistent structure and was examined in more detail. The angulation of the SCJ was measured in three orthogonal planes using CT multiplanar reformats. Each SCJ (160 in total) was assessed for transverse, coronal, and sagittal angulation of the central manubrial articular surface in respect to the long axis of the manubrial body using a newly devised measurement technique. RESULTS: The mean angles (± standard deviation) of the SCJs were 62.4 ± 9.7° to the transverse plane, 149.3 ± 7.3° to the coronal plane and 69.8 ± 7.5 to the sagittal plane. There was no significant difference in transverse (p = 0.41) or sagittal (p = 0.60) angulation between sides, however there was a significant difference for the coronal plane (p = 0.04). No significant differences were noted between the sexes in any plane. CONCLUSIONS: Increasing use of invasive diagnostic and treatment techniques dictate that a safe approach to the joint should be used to reduce the risk of iatrogenic injury. This study adds to existing knowledge of SCJ anatomy and its variation within the population. Understanding this can minimize the risk to adjacent structures when approaching the SCJ with injection needles or arthroscopic instruments.


Assuntos
Articulação Esternoclavicular/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Masculino , Planejamento de Assistência ao Paciente , Estudos Retrospectivos
3.
J Hand Surg Am ; 37(4): 807-10, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22305733

RESUMO

Dieterich disease is characterized by avascular necrosis of the metacarpal head. The recent literature has described surgical management of this condition relatively soon after its presentation. We present a case treated conservatively with a satisfactory outcome at 28 months.


Assuntos
Osteonecrose/terapia , Adolescente , Dedos/diagnóstico por imagem , Humanos , Masculino , Ossos Metacarpais/irrigação sanguínea , Articulação Metacarpofalângica/diagnóstico por imagem , Articulação Metacarpofalângica/fisiopatologia , Metacarpo/anormalidades , Metacarpo/diagnóstico por imagem , Osteonecrose/diagnóstico por imagem , Radiografia , Amplitude de Movimento Articular
4.
Science ; 178(4066): 1219-20, 1972 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-4637811

RESUMO

Two independent research groups replicate alteration of dark preference to dark avoidance by mice injected with synthetic scotophobin, a pentadecapeptide.


Assuntos
Aprendizagem da Esquiva/efeitos dos fármacos , Química Encefálica , Escuridão , Peptídeos/farmacologia , Animais , Injeções Intraperitoneais , Camundongos , Peptídeos/administração & dosagem
5.
Zh Nevrol Psikhiatr Im S S Korsakova ; 116(8 Pt 2): 30-32, 2016.
Artigo em Russo | MEDLINE | ID: mdl-27905385

RESUMO

AIM: To study a role of MTHFR mutations and their associations with the disturbances of basic parameters of the folate cycle in the development of ischemic stroke (IS). MATERIAL AND METHODS: Fifty-one post-stroke patients, 26 women and 25 men, aged from 29 to 87 years, were included in the study. The control group consisted of 47 healthy people, 23 women and 24 men, aged from 30 to 83 years. MTHFR: rs1801131 and rs1801133 polymorphisms were genotyped. Contents of folate, B12 and homocysteine were measured. RESULTS: The risk group which was characterized by the presence of risk variants of rs1801131 and rs1801133 polymorphisms, changes in the parameters of the folate cycle (the decrease in B12 concentration (≤500 pg/ml)) in the combination with hyperhomocysteinemia (≥13 mcmol/L) was identified. CONCLUSION: The disturbance of the folate cycle, including gene variations, is a basic pathogenetic link in the development of cerebral atherosclerosis and associated cerebrovascular diseases.


Assuntos
Isquemia Encefálica/metabolismo , Ácido Fólico/metabolismo , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Acidente Vascular Cerebral/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Hiper-Homocisteinemia , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Fatores de Risco
6.
Arthrosc Tech ; 4(5): e503-5, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26697312

RESUMO

The Outerbridge-Kashiwagi procedure, or ulnohumeral arthroplasty, was described in 1978 as a method of treating elbow arthritis by creating a fenestration in the olecranon fossa. This fenestration diminishes the likelihood of recurrent spurs in the olecranon fossa and coronoid fossa, without loss of structural bony strength. Arthroscopic techniques have now been developed to perform this procedure. We describe an efficient method of creating the fenestration between the olecranon fossa and coronoid fossa during an arthroscopic ulnohumeral arthroplasty, or Outerbridge-Kashiwagi procedure, that also reduces the amount of residual bone debris produced during the resection.

7.
Oncogene ; 34(45): 5626-34, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-25684139

RESUMO

Evasion of extracellular matrix detachment-induced apoptosis ('anoikis') is a defining characteristic of metastatic tumor cells. The ability of metastatic carcinoma cells to survive matrix detachment and escape anoikis enables them to disseminate as viable circulating tumor cells and seed distant organs. Here we report that αB-crystallin, an antiapoptotic molecular chaperone implicated in the pathogenesis of diverse poor-prognosis solid tumors, is induced by matrix detachment and confers anoikis resistance. Specifically, we demonstrate that matrix detachment downregulates extracellular signal-regulated kinase (ERK) activity and increases αB-crystallin protein and messenger RNA (mRNA) levels. Moreover, we show that ERK inhibition in adherent cancer cells mimics matrix detachment by increasing αB-crystallin protein and mRNA levels, whereas constitutive ERK activation suppresses αB-crystallin induction during matrix detachment. These findings indicate that ERK inhibition is both necessary and sufficient for αB-crystallin induction by matrix detachment. To examine the functional consequences of αB-crystallin induction in anoikis, we stably silenced αB-crystallin in two different metastatic carcinoma cell lines. Strikingly, silencing αB-crystallin increased matrix detachment-induced caspase activation and apoptosis but did not affect cell viability of adherent cancer cells. In addition, silencing αB-crystallin in metastatic carcinoma cells reduced the number of viable circulating tumor cells and inhibited lung metastasis in two orthotopic models, but had little or no effect on primary tumor growth. Taken together, our findings point to αB-crystallin as a novel regulator of anoikis resistance that is induced by matrix detachment-mediated suppression of ERK signaling and promotes lung metastasis. Our results also suggest that αB-crystallin represents a promising molecular target for antimetastatic therapies.


Assuntos
Anoikis , Neoplasias da Mama/metabolismo , Matriz Extracelular/metabolismo , Neoplasias Pulmonares/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas de Neoplasias/metabolismo , Cadeia B de alfa-Cristalina/metabolismo , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Adesão Celular/genética , Linhagem Celular Tumoral , Matriz Extracelular/genética , Matriz Extracelular/patologia , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Nus , Metástase Neoplásica , Proteínas de Neoplasias/genética , Cadeia B de alfa-Cristalina/genética
8.
Biol Psychiatry ; 24(8): 886-90, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2852967

RESUMO

This study evaluated the effects in rats of very low amplitude (10 mu amp) charge-balanced 10-Hz stimulation delivered bilaterally to low impedance points on the outer ear. This microelectrostimulation markedly and significantly reduced the number of opiate abstinence signs observed following a week of continuous morphine infusion. This effect was prevented by subcutaneous injection of 3 mg/kg naloxone, suggesting that stimulation of endogenous opioid activity plays a major role in the actions of auricular microelectrostimulation.


Assuntos
Encéfalo/fisiopatologia , Orelha Externa/inervação , Estimulação Elétrica , Dependência de Morfina/fisiopatologia , Morfina/toxicidade , Naloxona/farmacologia , Receptores Opioides/fisiologia , Síndrome de Abstinência a Substâncias/fisiopatologia , Animais , Encéfalo/efeitos dos fármacos , Masculino , Ratos , Ratos Endogâmicos , Receptores Opioides/efeitos dos fármacos
9.
Neurobiol Aging ; 12(2): 181-3, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-2052132

RESUMO

In previous studies, 18-month-old rats have shown no significant retention 24 hours after the single acquisition trial in a one-trial discriminative reward learning task. In the present study, ten 18-month-old rats pretreated with 0.5 mg/kg MSF IP showed significantly better retention in terms of speed and errors than eleven 18-month-old rats pretreated with injection vehicle alone. However, twelve two-three-month-old rats pretreated with the same dose of MSF failed to show better retention than eleven two-three-month-old rats pretreated with vehicle alone.


Assuntos
Inibidores da Colinesterase/farmacologia , Aprendizagem/efeitos dos fármacos , Sulfonas/farmacologia , Envelhecimento/psicologia , Animais , Encéfalo/enzimologia , Colinesterases/metabolismo , Aprendizagem por Discriminação/efeitos dos fármacos , Aprendizagem por Discriminação/fisiologia , Masculino , Memória/efeitos dos fármacos , Ratos , Ratos Endogâmicos , Recompensa , Estimulação Química
10.
Neurobiol Aging ; 14(4): 393-5, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8367021

RESUMO

Aged (24-month-old) rats were treated chronically with methanesulfonyl fluoride (MSF), an acetylcholinesterase (AChE) inhibitor with selectivity for central nervous system AChE, or with injection vehicle alone. Twelve 0.22 mg/kg IP injections were given over 4 weeks. MSF rats showed significantly greater speed and accuracy on a 1 trial/day discriminative reward learning task. The chronic MSF treatment resulted in a 56% decrease in brain AChE activity but no discernable locomotor side effects and no liver damage as indicated by aspartate transferase activity.


Assuntos
Envelhecimento/psicologia , Inibidores da Colinesterase/farmacologia , Aprendizagem por Discriminação/efeitos dos fármacos , Recompensa , Sulfonas/farmacologia , Acetilcolinesterase/metabolismo , Animais , Aspartato Aminotransferases/sangue , Encéfalo/enzimologia , Inibidores da Colinesterase/toxicidade , Locomoção/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Esquema de Reforço , Sulfonas/toxicidade
11.
Psychopharmacology (Berl) ; 112(2-3): 339-42, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-7871039

RESUMO

Recently, a rodent model of nicotine abstinence syndrome has been developed based on continuous subcutaneous infusion of nicotine tartrate and observing the frequency of spontaneous behavioral signs following termination of infusion. The observed signs closely resemble those commonly seen in rat opiate abstinence syndrome, raising the possibility that there is an endogenous opioid component in nicotine dependence. The present study demonstrates that the opiate antagonist naloxone can precipitate an abstinence syndrome in nicotine-dependent rats. Fourteen rats were infused for 7 days with 9 mg/kg/day nicotine tartrate in saline via an Alzet osmotic minipump. Fourteen rats were sham-operated and remained nicotine-naive. Half of each group received 4.5 mg/kg naloxone SC immediately before a "blind" 15-min observation, while the other half received saline alone. ANOVA revealed significant nicotine infusion, naloxone injection and interaction effects. Post-hoc analysis showed that the nicotine-infused rats injected with naloxone had significantly more signs than all other groups (P < 0.01). In a second experiment, 2 mg/kg morphine sulfate SC produced a significant (P < 0.01) 91.2% reduction of spontaneous abstinence signs observed 21 h after termination of nicotine infusion. These results are consistent with the hypothesized endogenous opioid component in nicotine dependence and abstinence syndrome.


Assuntos
Naloxona/farmacologia , Nicotina/efeitos adversos , Síndrome de Abstinência a Substâncias/psicologia , Animais , Masculino , Morfina/uso terapêutico , Ratos , Ratos Sprague-Dawley , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Transtornos Relacionados ao Uso de Substâncias/psicologia
12.
Psychopharmacology (Berl) ; 115(1-2): 180-4, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7862893

RESUMO

Recently, a rodent model of nicotine abstinence syndrome has been developed based on observing the frequency of spontaneous behavioral signs following termination of continuous subcutaneous infusion of nicotine tartrate. In the present study, the nicotinic antagonist mecamylamine precipitated an abstinence syndrome in nicotine-dependent rats. Twelve rats were each infused for 7 days with 9 mg/kg per day nicotine tartrate in saline via Alzet osmotic minipumps; another 12 rats were sham-operated and remained nicotine-naive. Six rats from each group received 1 mg/kg mecamylamine in saline SC immediately before a 30-min observation, while the remaining six rats from each group received saline alone. Nicotine-infused rats receiving mecamylamine exhibited significantly more (P < 0.01), overall abstinence signs than all other groups. In terms of categories of signs, they displayed significantly more gasps/writhes, teeth chatter/chews, shakes/tremors and ptosis. In a second experiment utilizing only nicotine-naive rats, a far higher dose of mecamylamine (5 mg/kg sc) induced a quasi-nicotine abstinence syndrome. The results provide further validation for this rodent model of nicotine abstinence syndrome.


Assuntos
Mecamilamina/farmacologia , Nicotina/efeitos adversos , Antagonistas Nicotínicos/farmacologia , Síndrome de Abstinência a Substâncias/psicologia , Animais , Comportamento Animal/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Transtornos Relacionados ao Uso de Substâncias/psicologia
13.
Psychopharmacology (Berl) ; 140(3): 371-7, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9877017

RESUMO

Nitric oxide synthesis contributes to opiate tolerance and dependence. Nicotine dependence and abstinence syndrome in the rat appear to involve opiate mechanisms. Therefore, it was postulated that nitric oxide synthase (NOS) activity might be essential for the expression of nicotine abstinence syndrome. Twenty-one rats were rendered dependent by SC infusion of 9 mg/kg per day nicotine tartrate via Alzet osmotic minipump. Rats were pretreated SC with vehicle alone, or with 18 or 30 mg/kg of the NOS inhibitor L-NNA (nitro-L-arginine). Thirty minutes later, rats were challenged by 1 mg/kg of the nicotinic antagonist mecamylamine SC and observed for 30 additional minutes. Rats pretreated with vehicle displayed a total of 68.7+/-8.0 mecamylamine-precipitated abstinence signs (mean+/-SEM), while those receiving 18 or 30 mg/kg L-NNA had 12.7+/-2.0 and 5.1+/-1.7 signs, respectively. All three groups differed significantly from one another according to Dunn's post-hoc procedure. Rats pretreated with L-NNA combined with an excess of the NOS substrate L-arginine had significantly more mecamylamine-precipitated abstinence signs than rats receiving L-NNA combined with D-arginine. Also, D-NNA, which does not selectively bind to NOS, was significantly less effective than L-NNA in preventing mecamylamine-precipitated abstinence syndrome. Additional studies determined the effect of L-NNA on spontaneous nicotine abstinence syndrome. Rats were assessed for abstinence signs at 17 and 20 h after termination of nicotine infusion. They received injections of 9, 18, or 30 mg/kg L-NNA SC or vehicle alone immediately before the 20-h observation; all rats were observed for 30 min. Signs at 20 h (post-injection) as a percentage of signs at 17 h (pre-injection) declined significantly as a function of L-NNA dose. Once again, this effect was attenuated significantly more by co-administration of L-arginine than by D-arginine. The overall pattern of results suggests that nitric oxide synthesis is critical to the expression of nicotine abstinence syndrome.


Assuntos
Mecamilamina/farmacologia , Antagonistas Nicotínicos/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Síndrome de Abstinência a Substâncias/prevenção & controle , Tabagismo/complicações , Animais , Masculino , Nicotina/efeitos adversos , Agonistas Nicotínicos/efeitos adversos , Ratos , Ratos Sprague-Dawley , Síndrome de Abstinência a Substâncias/etiologia
14.
Psychopharmacology (Berl) ; 151(4): 344-50, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11026741

RESUMO

Nociceptin/orphanin FQ (N/OFQ) is a neuropeptide that exerts antiopiate effects under some circumstances, and there is evidence that it contributes to opiate tolerance. This raises the question, might N/OFQ also contribute to opiate dependence and abstinence? Twenty-two male Sprague-Dawley rats were cannulated in the third ventricle and challenged 7 days later by third ventricle injection of 50, 200 or 1,000 ng N/OFQ or saline alone. Each rat was observed under "blind" conditions for 30 min beginning 15 min after onset of the third ventricle injection. There was a significant positive linear trend of signs as a function of N/OFQ dose. Subjects receiving saline had 18.0+/-2.0 (mean+/-SEM) overall abstinence-like signs, whereas subjects receiving 50, 200 or 1000 ng N/OFQ had 35.2+/-3.6, 49.8+/-2.6 and 63.5+/-9.7 signs, respectively. In 16 additional rats, abstinence-like signs induced by 1000 ng N/OFQ were significantly attenuated by low SC doses of morphine or clonidine. These results raise the possibility that N/OFQ might contribute to opiate dependence and subsequent abstinence syndrome. On the other hand, N/OFQ over a wide dose range induced abstinence signs with similar potency in morphine dependent and non-dependent rats.


Assuntos
Morfina/efeitos adversos , Peptídeos Opioides/farmacologia , Síndrome de Abstinência a Substâncias/etiologia , Animais , Clonidina/farmacologia , Relação Dose-Resposta a Droga , Masculino , Dependência de Morfina/tratamento farmacológico , Ratos , Ratos Sprague-Dawley , Nociceptina
15.
Peptides ; 12(5): 1011-4, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1800944

RESUMO

The octapeptide FLFQPQRFamide (neuropeptide FF or F8Fa) may play a role in opiate dependence and subsequent abstinence syndrome. Previously, NPFF precipitated opiate abstinence syndrome, while IgG from NPFF antiserum attenuated subsequent naloxone-precipitated abstinence signs in dependent rats. The peptide desamino YFLFQPQRamide (daY8Ra) was synthesized as a possible NPFF antagonist. At a dose of 600 ng ICV, daY8Ra significantly attenuated (p less than 0.001) the number of abstinence-like signs subsequently induced by 10 micrograms NPFF ICV, suggesting that daY8Ra does have antagonist activity against NPFF. Pretreatment of morphine-dependent rats with the same dose of daY8Ra also significantly attenuated (p less than 0.001) the abstinence signs subsequently precipitated by 10 micrograms naloxone ICV. Pretreatment with 600 ng of NPFF itself, or of NPFF modified at the N-terminal only (daY9Fa), failed to attenuate subsequent naloxone-precipitated abstinence, suggesting that the C-terminal modification is critical for NPFF antagonist activity. It should be noted, however, that higher doses of daY8Ra (2 micrograms or more) can precipitate some abstinence signs in a manner similar to NPFF.


Assuntos
Ventrículos Cerebrais/fisiologia , Dependência de Morfina/fisiopatologia , Oligopeptídeos/farmacologia , Síndrome de Abstinência a Substâncias/fisiopatologia , Sequência de Aminoácidos , Animais , Ventrículos Cerebrais/efeitos dos fármacos , Ventrículos Cerebrais/fisiopatologia , Injeções Intraventriculares , Masculino , Dados de Sequência Molecular , Morfina/farmacologia , Naloxona/farmacologia , Oligopeptídeos/administração & dosagem , Oligopeptídeos/síntese química , Ratos , Ratos Endogâmicos , Síndrome de Abstinência a Substâncias/prevenção & controle
16.
Peptides ; 14(1): 47-51, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8382812

RESUMO

FMRFa is a molluscan peptide that has shown antiopiate activity in a number of mammalian test systems. The current study determined the antiopiate potency of FMRFa and two conformationally constrained peptidomimetics of FMRFa containing stereoisomers of Z-2,3-methanomethionine. Morphine abstinence signs were observed after varying doses (0.25-25.0 micrograms) of these substances were injected into the third ventricle of morphine-dependent rats. Although both peptidomimetics were far more potent than FMRFa itself, they bound with lower affinity than FMRFa to rat spinal cord receptors for the mammalian FMRFa-like peptide, NPFF.


Assuntos
Endorfinas/antagonistas & inibidores , Neuropeptídeos/farmacologia , Sequência de Aminoácidos , Animais , FMRFamida , Técnicas In Vitro , Masculino , Metionina/análogos & derivados , Dados de Sequência Molecular , Estrutura Molecular , Dependência de Morfina/etiologia , Neuropeptídeos/química , Neuropeptídeos/metabolismo , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Oligopeptídeos/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de Neurotransmissores/efeitos dos fármacos , Receptores de Neurotransmissores/metabolismo
17.
Peptides ; 11(2): 277-80, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2356156

RESUMO

Yang et al. (14) have isolated from mammalian brain an octapeptide FLFQPQRF-NH2 (F-8-F-NH2) with certain antiopiate properties. Third ventricular injection of 2 micrograms of this peptide together with the aminopeptidase inhibitor bestatin precipitated an opiate-withdrawal syndrome in morphine-dependent but not in nondependent rats. Third ventricular injection in nondependent rats of 15 micrograms of the peptide together with bestatin induced a morphine-withdrawal-like behavioral syndrome. This syndrome was not produced by injection of bestatin or saline vehicle alone and was preventable by injection of 3.5 mg/kg morphine sulphate SC.


Assuntos
Morfina/efeitos adversos , Neuropeptídeos/farmacologia , Oligopeptídeos/farmacologia , Síndrome de Abstinência a Substâncias/etiologia , Análise de Variância , Animais , Método Duplo-Cego , Injeções Intraventriculares , Leucina/análogos & derivados , Leucina/farmacologia , Masculino , Morfina/farmacologia , Neuropeptídeos/administração & dosagem , Neuropeptídeos/antagonistas & inibidores , Oligopeptídeos/administração & dosagem , Oligopeptídeos/antagonistas & inibidores , Distribuição Aleatória , Ratos , Ratos Endogâmicos
18.
Peptides ; 14(4): 731-4, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8234017

RESUMO

FMRFamide is a molluscan peptide that has shown antiopiate activity in a number of mammalian test systems. The current study determined the antiopiate potency of FMRFamide and two conformationally constrained peptidomimetics of FMRFamide containing stereoisomers of (E)-2,3-methanomethionine. Morphine abstinence signs were observed after varying doses (0.25-25.0 microgram) of these substances were injected into the third ventricle of morphine-dependent rats. Both peptidomimetics were far more potent than FMRFamide itself. In addition, although both peptidomimetics bound with lower affinity than FMRFamide to rat spinal cord receptors for NPFF (the mammalian FMRFamide-like peptide), they were far more resistant than FMRFamide to enzymatic degradation by leucine aminopeptidase.


Assuntos
Leucil Aminopeptidase/metabolismo , Metionina/análogos & derivados , Antagonistas de Entorpecentes/farmacologia , Neuropeptídeos/farmacologia , Sequência de Aminoácidos , Animais , FMRFamida , Hidrólise , Masculino , Metionina/análise , Dados de Sequência Molecular , Neuropeptídeos/metabolismo , Oligopeptídeos/metabolismo , Ligação Proteica , Ratos , Ratos Sprague-Dawley , Receptores de Neuropeptídeos/metabolismo , Receptores Opioides/metabolismo , Estereoisomerismo , Síndrome de Abstinência a Substâncias/etiologia
19.
Peptides ; 17(1): 83-6, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8822514

RESUMO

FMRFamide is a molluscan peptide that has shown antiopiate activity in a number of mammalian test systems. Peptidomimetics of FMRFamide substituted with conformationally constrained stereoisomers of Z-2,3-methanomethionine or E-2,3-methanomethionine precipitated abstinence syndrome far more potently than FMRFamide itself. The current study determined the effect on antiopiate potency of an additional rigid substitution. A peptidomimetic containing a stereoisomer of E-2,3-methanomethionine was compared with a peptidomimetic additionally substituted at the C-terminal with E-2,3-methanophenylalanine. Morphine abstinence signs were observed after varying doses (0.125-25.0 micrograms) of these two peptidomimetics were injected into the third ventricle of morphine-dependent rats. The peptidomimetic containing both rigid substitutions was far more potent than the peptidomimetic of FMRFamide containing methanomethionine alone. The increased potency appears to be related to enzyme resistance rather than receptor affinity.


Assuntos
Hormônios de Invertebrado/farmacologia , Neuropeptídeos/farmacologia , Peptídeos Opioides/antagonistas & inibidores , Sequência de Aminoácidos , Animais , FMRFamida , Hormônios de Invertebrado/química , Hormônios de Invertebrado/genética , Leucil Aminopeptidase/metabolismo , Masculino , Metionina/análogos & derivados , Metionina/química , Dados de Sequência Molecular , Dependência de Morfina/metabolismo , Neuropeptídeos/química , Neuropeptídeos/genética , Oligopeptídeos/química , Oligopeptídeos/genética , Fenilalanina/análogos & derivados , Fenilalanina/química , Ratos , Ratos Sprague-Dawley , Receptores de Neuropeptídeos/metabolismo , Estereoisomerismo
20.
Peptides ; 17(4): 615-8, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8804070

RESUMO

Neuropeptide FF (NPFF) has certain antiopiate actions and may play a role in opiate tolerance and dependence. Third ventricle injection of 10 micrograms NPFF induces a quasimorphine abstinence syndrome in opiate-naive rats. Nitric oxide synthesis may also contribute to opiate tolerance and dependence. The present study tests the hypothesis that NPFF acts through stimulation of nitric oxide synthase (NOS). Third ventricular injection of 10 micrograms NPFF precipitated an average of 46 abstinence-like signs during a 20-min observation. Pretreatment (30 min earlier) with 7.5 or 15 mg/kg s.c. of the NOS inhibitor nitro-L-arginine (L-NNA) resulted in a significant and dose-dependent alleviation of NPFF-induced abstinence-like signs. The anti-NPFF activity of 15 mg/kg L-NNA was blocked by 750 mg/kg L-arginine, but not by the same amount of D-arginine, indicating that L-NNA attenuates NPFF activity through a stereospecific inhibition of NOS.


Assuntos
Ventrículos Cerebrais/fisiologia , Inibidores Enzimáticos/farmacologia , Antagonistas de Entorpecentes/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Nitroarginina/farmacologia , Oligopeptídeos/farmacologia , Comportamento Estereotipado/efeitos dos fármacos , Síndrome de Abstinência a Substâncias , Animais , Arginina/farmacologia , Ventrículos Cerebrais/efeitos dos fármacos , Injeções Intraventriculares , Masculino , Antagonistas de Entorpecentes/administração & dosagem , Oligopeptídeos/administração & dosagem , Ratos , Ratos Sprague-Dawley , Estereoisomerismo
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