Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 113
Filtrar
Más filtros

Banco de datos
Tipo del documento
Intervalo de año de publicación
1.
Am J Otolaryngol ; 37(1): 41-3, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26700259

RESUMEN

BACKGROUND: Lymphangioma of the head and neck is considered a rare congenital tumor with the vast majority presenting before two years of age. Surgical excision and sclerosing therapy using OK-432 are recognized as effective treatment options for the majority of these lesions; however, treatment options of laryngeal lesions are less straightforward due to the risk of airway compromise and the desire to maintain the integrity of a functional larynx. We present the case of a four month old male who presented with chief complaint of inspiratory stridor after a single episode of pneumonia. His clinical presentation, flexible fiberoptic laryngoscopic examination, and operative evaluation were consistent with a lymphangioma completely encasing the epiglottis and arytenoids and isolated to the supraglottis. This report outlines our approach to workup and treatment of this rare lesion. METHOD: Case report of presentation, diagnosis and treatment is presented. RESULTS: A four-month old male presented to ENT clinic with inspiratory stridor, worsened with crying, without frank respiratory distress. History and initial examination was consistent with airway obstruction. Flexible fiberoptic laryngoscopy showed laryngomalacia as well as diffuse and symmetric supraglottic edema. Surgical evaluation identified edema limited to the supraglottis, notably along the ventral surface of the epiglottis and dorsal surface of bilateral arytenoids. Biopsies were taken and immunohistochemical staining was performed with strong positivity for D2-40 and CD31, supporting the diagnosis of isolated lymphangioma of the supraglottis. Treatment was performed through multiple point spot welding with a fiber equipped CO2 LASER (OmniGuide TM) at 5 watt continuous power. CONCLUSION: Isolated supraglottic lymphangioma was diagnosed via direct laryngoscopy, with pathologic and immunohistochemical confirmation. Carbon dioxide laser spot welding technique was used with excellent clinical improvement in stridor. Clinical improvement is sustained after 6 months follow-up.


Asunto(s)
Neoplasias Laríngeas/diagnóstico , Linfangioma/diagnóstico , Obstrucción de las Vías Aéreas/etiología , Humanos , Lactante , Neoplasias Laríngeas/congénito , Neoplasias Laríngeas/cirugía , Laringoscopía , Terapia por Láser , Linfangioma/congénito , Linfangioma/cirugía , Masculino , Ruidos Respiratorios/etiología
2.
Nat Med ; 2(10): 1129-32, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8837612

RESUMEN

Cocaine abuse is a major medical and public health concern in the United States, with approximately 2.1 million people dependent on cocaine. Pharmacological approaches to the treatment of cocaine addiction have thus far been disappointing, and new therapies are urgently needed. This paper describes an immunological approach to cocaine addiction. Antibody therapy for neutralization of abused drugs has been described previously, including a recent paper demonstrating the induction of anti-cocaine antibodies. However, both the rapidity of entry of cocaine into the brain and the high doses of cocaine frequently encountered have created challenges for an antibody-based therapy. Here we demonstrate that antibodies are efficacious in an animal model of addiction. Intravenous cocaine self-administration in rats was inhibited by passive transfer of an anti-cocaine monoclonal antibody. To actively induce anti-cocaine antibodies, a cocaine vaccine was developed that generated a high-titer, long-lasting antibody response in mice. Immunized mice displayed a significant change in cocaine pharmacokinetics, with decreased levels of cocaine measured in the brain of immunized mice only 30 seconds after intravenous (i.v.) administration of cocaine. These data establish the feasibility of a therapeutic cocaine vaccine for the treatment of cocaine addiction.


Asunto(s)
Cocaína/inmunología , Haptenos/inmunología , Inmunoterapia Activa , Trastornos Relacionados con Opioides/terapia , Vacunas/inmunología , Animales , Cocaína/administración & dosificación , Condicionamiento Operante , Estudios de Evaluación como Asunto , Haptenos/administración & dosificación , Inyecciones Intravenosas , Masculino , Ratones , Ratones Endogámicos BALB C , Trastornos Relacionados con Opioides/inmunología , Ratas , Ratas Wistar , Autoadministración , Albúmina Sérica Bovina/administración & dosificación , Albúmina Sérica Bovina/inmunología
3.
Science ; 251(4997): 1065-7, 1991 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-17802093

RESUMEN

The terrestrial halophyte, Salicornia bigelovii Torr., was evaluated as an oilseed crop for direct seawater irrigation during 6 years of field trials in an extreme coastal desert environment. Yields of seed and biomass equated or exceeded freshwater oilseed crops such as soybean and sunflower. The seed contained 26 to 33 percent oil, 31 percent protein, and was low in fiber and ash (5 to 7 percent). The oil and meal were extracted by normal milling equipment, and the oil was high in linoleic acid (73 to 75 percent) and could replace soybean oil in chicken diets. The meal had antigrowth factors, attributed to saponins, but could replace soybean meal in chicken diets amended with the saponin antagonist, cholesterol. Salicornia bigelovii appears to be a potentially valuable new oilseed crop for subtropical coastal deserts.

4.
Science ; 291(5506): 1026-31, 2001 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-11161213

RESUMEN

Large particles containing nitric acid (HNO3) were observed in the 1999/2000 Arctic winter stratosphere. These in situ observations were made over a large altitude range (16 to 21 kilometers) and horizontal extent (1800 kilometers) on several airborne sampling flights during a period of several weeks. With diameters of 10 to 20 micrometers, these sedimenting particles have significant potential to denitrify the lower stratosphere. A microphysical model of nitric acid trihydrate particles is able to simulate the growth and sedimentation of these large sizes in the lower stratosphere, but the nucleation process is not yet known. Accurate modeling of the formation of these large particles is essential for understanding Arctic denitrification and predicting future Arctic ozone abundances.

5.
Cancer Res ; 36(5): 1744-7, 1976 May.
Artículo en Inglés | MEDLINE | ID: mdl-1268831

RESUMEN

The production of lung adenomas in strain A mice following multiple i.p. injections of 13 metallic compounds was investigated. A significant increase in the average number of lung tumors per mouse was noted following the administration of lead subacetate, manganous sulfate, molybdenum trioxide, and nickelous acetate. These four compounds can be considered as weakly carcinogenic for lung tumors in strain A mice.


Asunto(s)
Adenoma/inducido químicamente , Neoplasias Pulmonares/inducido químicamente , Metales/toxicidad , Animales , Femenino , Plomo/toxicidad , Masculino , Intoxicación por Manganeso , Ratones , Molibdeno/toxicidad , Neoplasias Experimentales/inducido químicamente , Níquel/toxicidad , Uretano
6.
Springerplus ; 5(1): 973, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27429883

RESUMEN

Cover crops are a major focus of conservation agriculture efforts because they can provide soil cover and increase nutrient availability after their mineralization in cropping systems. To evaluate the effect of residue type and placement on rate of decomposition and carbon (C) and nitrogen (N) mineralization, residues from two food crops, maize (Zea mays L.) and common bean (Phaseolus vulgaris L.), and two promising cover crops, sunn hemp (Crotalaria juncea L.) and sorghum sudangrass (Sorghum bicolor [L.] Moench x S. bicolor var. Sudanese [Piper] Stapf) were used in a litterbag study in the Central Plateau region of Haiti from May to September, 2013. Residues were placed in litterbags at a rate equivalent to 3.25 Mg residue ha(-1) either on the soil surface or buried at 15 cm to represent a tilled and no-tillage system, respectively. Initial C:N ratios were: maize > common bean > sorghum sudangrass > sunn hemp. Highest residue mass loss rates and C and N mineralization generally occurred in the reverse order. Overall, surface-placed residues decomposed more slowly with 40 and 17 % of initial residue mass of surface and buried residues, respectively, remaining at 112 days. Carbon and N mineralization was higher when residues were buried. Net N mineralization of buried residues was 0.12, 0.07, 0.06, and 0.03 g N g residue(-1) for sunn hemp, sorghum sudangrass, maize, and common bean, respectively over 112 days. To achieve the goal of increasing nutrient supply while maintaining year-round cover, a combination of grass and legume cover crops may be required with benefits increasing over multiple seasons.

7.
J Mol Biol ; 207(3): 505-12, 1989 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-2668533

RESUMEN

The oriT locus of the Escherichia coli K12 F plasmid contains a site at which one of the DNA strands is cleaved as a prelude to conjugal transmission to recipient bacteria. We have remapped this site biochemically by using oriT-containing plasmids that were purified from bacteria expressing the F transfer (tra) functions. The strand interruption was found on the transferred strand 137 base-pairs clockwise of the center of the BglII site at 66.7 on the F map. This location is consistent with the locations anticipated from studies of delta traF' plasmids, but it differs from previous results by other investigators. The strand interruption produced a 3'-OH, but the nature of the 5' terminus of the strand on the other side of the nick was not determined. Some DNA sequence motifs in the vicinity of the oriT nick site of F resemble the chromosomal site involved in formation of delta traF'purE plasmids.


Asunto(s)
ADN Bacteriano/metabolismo , Escherichia coli/metabolismo , Factor F , Secuencia de Bases , Sitios de Unión , ADN Bacteriano/genética , Escherichia coli/genética , Datos de Secuencia Molecular , Mapeo Restrictivo
8.
J Phys Chem B ; 109(13): 6061-8, 2005 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-16851666

RESUMEN

Ultraviolet light-induced electron-hole pair excitations in anatase TiO(2) powders were studied by a combination of electron paramagnetic resonance and infrared spectroscopy measurements. During continuous UV irradiation in the mW.cm(-2) range, photogenerated electrons are either trapped at localized sites, giving paramagnetic Ti(3+) centers, or remain in the conduction band as EPR silent species which may be observed by their IR absorption. Using low temperatures (90 K) to reduce the rate of the electron-hole recombination processes, trapped electrons and conduction band electrons exhibit lifetimes of hours. The EPR-detected holes produced by photoexcitation are O(-) species, produced from lattice O(2-) ions. It is found that under high vacuum conditions, the major fraction of photoexcited electrons remains in the conduction band. At 298 K, all stable hole and electron states are lost from TiO(2). Defect sites produced by oxygen removal during annealing of anatase TiO(2) are found to produce a Ti(3+) EPR spectrum identical to that of trapped electrons, which originate from photoexcitation of oxidized TiO(2). Efficient electron scavenging by adsorbed O(2) at 140 K is found to produce two long-lived O(2)(-) surface species associated with different cation surface sites. Reduced TiO(2), produced by annealing in vacuum, has been shown to be less efficient in hole trapping than oxidized TiO(2).

9.
Am J Psychiatry ; 138(11): 1505-6, 1981 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-6895278

RESUMEN

The authors describe a patient who developed delirium secondary to the topical absorption of podophyllin; this may be the first known case of delirium after topical application of the drug. Other serious medical and neurological complications of podophyllin poisoning are also discussed.


Asunto(s)
Delirio/inducido químicamente , Podofilino/efectos adversos , Administración Tópica , Adulto , Femenino , Humanos , Podofilino/uso terapéutico , Psicosis Inducidas por Sustancias/psicología , Enfermedades de Transmisión Sexual/tratamiento farmacológico , Verrugas/tratamiento farmacológico
10.
Am J Psychiatry ; 145(11): 1369-78, 1988 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2903685

RESUMEN

In their own practices and in consultation, requests to psychiatrists to evaluate and treat sleep disorders in the elderly are common. The five million elders in this country receive 35%-40% of the sedative-hypnotics prescribed, despite the fact that they represent only 12% of the population. Since their sleep disturbances are usually secondary to medical, psychiatric, pharmacologic, or environmental causes, they should receive a thorough evaluation and differential diagnostic approach. Before prescribing a sedative-hypnotic, one should consider nonpharmacologic interventions and education about normal sleep changes due to aging. As a foundation for the judicious prescribing of sedative-hypnotics, the pharmacokinetic changes associated with aging are discussed.


Asunto(s)
Trastornos del Sueño-Vigilia/terapia , Anciano , Envejecimiento/fisiología , Ansiolíticos/uso terapéutico , Benzodiazepinas , Diagnóstico Diferencial , Humanos , Hipnóticos y Sedantes/uso terapéutico , Sueño/fisiología , Trastornos del Sueño-Vigilia/diagnóstico , Trastornos del Sueño-Vigilia/tratamiento farmacológico
11.
Am J Psychiatry ; 140(2): 158-61, 1983 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-6849425

RESUMEN

Seventeen areas of psychosocial distress were evaluated in 87 university hospital internal medicine clinic patients by a self-administered questionnaire and a psychiatric interview. These patients' internists then predicted the patients' distress level in each area. Their predictions correlated significantly with their patients' self-reports of distress-level problems in only 3 of the 17 areas. Even when the internists felt that they had sufficient information to make an accurate prediction, their perceptions were often erroneous, including evaluations of such areas as suicidal ideation and drug use. These data suggest the need for active psychiatric education components in internal medicine training programs.


Asunto(s)
Atención Ambulatoria , Medicina Interna , Trastornos Mentales/diagnóstico , Actitud del Personal de Salud , Actitud Frente a la Salud , Femenino , Humanos , Medicina Interna/educación , Internado y Residencia , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Inventario de Personalidad , Relaciones Médico-Paciente , Ajuste Social , Estrés Psicológico/diagnóstico
12.
Am J Med ; 76(5): 921-3, 1984 May.
Artículo en Inglés | MEDLINE | ID: mdl-6720732

RESUMEN

Reported herein is the possible interaction between two drugs used to treat a man with a large prolactin-secreting pituitary adenoma. The patient had a long history of schizophrenia that was treated with many different medications, including phenothiazines. Evaluation of progressive lethargy led to the discovery of a large parasellar tumor and a prolactin level of 7,981 ng/ml. His serum prolactin level fell to the 400 ng/ml range during bromocriptine therapy but rose whenever the antipsychotic thioridazine was added to his regimen. A marked deterioration of his visual fields was noted after 3 months' therapy with both drugs, and this abnormality resolved five days after the thioridazine was stopped. The use of dopamine antagonists such as thioridazine in patients with prolactinoma may interfere with bromocriptine's action, resulting in potentially serious complications.


Asunto(s)
Adenoma/tratamiento farmacológico , Bromocriptina/uso terapéutico , Neoplasias Hipofisarias/tratamiento farmacológico , Prolactina/sangre , Tioridazina/efectos adversos , Adenoma/complicaciones , Adenoma/metabolismo , Adulto , Interacciones Farmacológicas , Humanos , Masculino , Neoplasias Hipofisarias/complicaciones , Neoplasias Hipofisarias/metabolismo , Esquizofrenia Paranoide/complicaciones , Esquizofrenia Paranoide/tratamiento farmacológico , Tioridazina/uso terapéutico , Tomografía Computarizada por Rayos X , Campos Visuales/efectos de los fármacos
13.
Crit Rev Neurobiol ; 10(2): 189-203, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8971129

RESUMEN

Estrogen regulates neuroendocrine, reproductive, and behavioral functions of the brain by utilizing a number of diverse cellular mechanisms. In the classical genomic mechanism of steroids, estrogen induces relatively long-term actions on neurons by activating specific intracellular receptors that modulate transcription and protein synthesis. In addition, estrogen can also exert very rapid effects in the brain that cannot be attributed to genomic mechanisms. These nongenomic actions of estrogen influence a variety of neuronal properties, including electrical excitability, synaptic functioning, and morphological features, and are involved in many of the physiological functions and clinical effects of estrogen in the brain. Recently the specific cellular and molecular mechanisms underlying the nongenomic actions of estrogen have begun to be elucidated. Estrogen may utilize direct membrane mechanisms, such as activation of ligand-gated ion channels and G-protein-coupled second messenger systems and regulation of neurotransmitter transporters. Additionally the membrane and genomic actions of estrogen have the potential to interact, producing synergistic effects and dependence between the two types of mechanisms. The combination of nongenomic and genomic mechanisms endows estrogen with considerable diversity, range, and power in regulating neural function.


Asunto(s)
Encéfalo/fisiología , Estrógenos/fisiología , Neuronas/fisiología , Animales , Encéfalo/citología , Genoma , Humanos , Canales Iónicos/fisiología , Terminales Presinápticos/fisiología , Receptores de Neurotransmisores/fisiología , Sistemas de Mensajero Secundario
14.
J Clin Psychiatry ; 47 Suppl: 31-8, 1986 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-3531190

RESUMEN

A number of advances, primarily pharmacologic, have occurred in recent years in the treatment of depression. Some of the recent advances relating to neurotransmitters and other neuropsychiatric factors believed to be related to depression are discussed, including how antidepressants may affect these systems. Some more recently recognized or often overlooked side effects of antidepressants are also discussed, as well as differential side effect profiles. The second generation antidepressants are critiqued and are generally believed to be no better than many of the first generation antidepressants. The usefulness of and indications for tricyclic serum levels and standard neuroendocrine tests for depression are summarized. Recent findings regarding lithium, including augmentation, and monoamine oxidase inhibitors, especially for atypical depressions with panic symptoms, are included, as is the use of psychostimulants, especially for medically ill patients who cannot take other antidepressants.


Asunto(s)
Antidepresivos Tricíclicos/uso terapéutico , Antidepresivos/uso terapéutico , Trastorno Depresivo/tratamiento farmacológico , Adulto , Antidepresivos/efectos adversos , Antidepresivos/farmacología , Antidepresivos Tricíclicos/efectos adversos , Antidepresivos Tricíclicos/farmacología , Trastorno Depresivo/psicología , Quimioterapia Combinada , Femenino , Humanos , Masculino
15.
Peptides ; 13(5): 891-6, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1336187

RESUMEN

Specific binding of 125I-[D-Ala6-CH3-Leu7-Pro9,NHET]LHRH, a LHRH agonist, to hippocampal membranes prepared from ovariectomized female rates was examined. One high affinity binding site was observed with a Kd of 0.12 +/- 0.01 nM and an apparent Bmax of 13.0 +/- 3.8 fmol/mg. Luteinizing hormone-releasing hormone and the behaviorally active Ac-LHRH(5-10) were able to compete for the agonist binding site. Native LHRH had an apparent Ki of 1.73 nM, while AC-LHRH(5-10) was 30 times less potent. Competition studies examined over the rat estrous cycle revealed an eighteenfold decrease in apparent affinity during diestrus I and estrus compared with ovariectomized animals. Tissue from animals in proestrus had a Ki of 5.0 nM. Specific binding studies indicate that receptor concentration is highest in proestrus (6.11 +/- 0.90 fmol/mg) and significantly lower during estrus (2.4 +/- 0.29 fmol/mg). These data suggest that at least one fragment of native LHRH can interact with neuronal LHRH receptors and that these receptors, like those in the pituitary, can be modulated by circulating steroid hormones.


Asunto(s)
Estro/metabolismo , Hormona Liberadora de Gonadotropina/análogos & derivados , Hipocampo/metabolismo , Pamoato de Triptorelina/análogos & derivados , Animales , Sitios de Unión , Unión Competitiva , Femenino , Hormona Liberadora de Gonadotropina/metabolismo , Cinética , Ovariectomía , Ratas , Ratas Sprague-Dawley , Receptores LHRH/metabolismo
16.
Brain Res ; 834(1-2): 164-7, 1999 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-10407108

RESUMEN

Dopamine (DA) uptake and clearance were examined using in vivo voltammetry following injection of DA (200 microM) into the nucleus accumbens of ovariectomized (OVX) or OVX-estrogen-primed rats (estradiol benzoate, EB, 10 microg 48 and 24 h prior to experiment). The rate of DA uptake was significantly attenuated in steroid-treated animals: this decrease was accompanied by a significant increase in DA clearance time. Quinpirole (0.5 mg/kg) modulated the kinetics of DA uptake in OVX but not EB-primed rats. These data suggest that DA clearance can be regulated by physiological doses of EB.


Asunto(s)
Dopamina/farmacocinética , Estradiol/farmacología , Animales , Agonistas de Dopamina/farmacología , Electrofisiología/métodos , Femenino , Núcleo Accumbens/efectos de los fármacos , Núcleo Accumbens/metabolismo , Ovariectomía , Quinpirol/farmacología , Ratas , Ratas Sprague-Dawley
17.
Brain Res ; 686(1): 93-8, 1995 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-7583276

RESUMEN

In vivo voltammetry was used to measure stimulated dopamine (DA) release in the nucleus accumbens following 6-hydroxydopamine (6-OHDA) lesions of the medial prefrontal cortex (PFC). Lesions of the PFC resulted in a significant potentiation of K(+)-stimulated DA release (383% of control). These data are in agreement with other studies which suggest DAergic activation of cortical sites can alter the activity of DAergic neurons at subcortical sites. Specifically these results suggest that DAergic nerve terminals in the nucleus accumbens are tonically inhibited by DAergic activity in the PFC and that alleviation of this tonic inhibition produces hyperresponsiveness in the nucleus accumbens.


Asunto(s)
Dopamina/metabolismo , Núcleo Accumbens/efectos de los fármacos , Corteza Prefrontal/efectos de los fármacos , Animales , Electroquímica/métodos , Femenino , Núcleo Accumbens/metabolismo , Oxidopamina , Potasio/farmacología , Corteza Prefrontal/metabolismo , Ratas , Ratas Sprague-Dawley , Estimulación Química
18.
Brain Res ; 478(1): 103-11, 1989 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-2564295

RESUMEN

The present studies were carried out to determine if tyrosine hydroxylase phosphorylation in rat brain striatal synaptosomes is activated by dibutyryl cyclic AMP treatment. Incubation of synaptosomes with [32P]orthophosphate, followed by immunoprecipitation and sodium dodecyl sulfate polyacrylamide gel electrophoresis, produced a band of radioactivity associated with a 62 kDa polypeptide. Treatment with the catecholamine neurotoxin, 6-hydroxydopamine, produced parallel losses of: (1) tyrosine hydroxylase enzyme activity, (2) dopamine content, and (3) the 62 kDa band of radioactivity. These data support the identification of this band as a tyrosine hydroxylase-derived polypeptide. Incubation with dibutyryl cyclic AMP produced an increase in soluble tyrosine hydroxylase activity and phosphorylation. These results suggest that the increase in synaptosomal catecholamine synthesis produced by dibutyryl cyclic AMP is mediated by an increase in tyrosine hydroxylase phosphorylation.


Asunto(s)
Bucladesina/farmacología , Cuerpo Estriado/metabolismo , Sinaptosomas/enzimología , Tirosina 3-Monooxigenasa/metabolismo , Animales , Dopamina/metabolismo , Hidroxidopaminas/farmacología , Masculino , Peso Molecular , Oxidopamina , Fosforilación , Ratas , Ratas Endogámicas
19.
Brain Res ; 538(2): 343-6, 1991 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-2012977

RESUMEN

Rats were treated twice daily either with saline or d-amphetamine (5 mg/kg) for 5 days. When challenged approximately 15 days later with an injection of 0.5 mg/kg amphetamine, the chronic amphetamine animals showed (1) an augmented release of dopamine in the caudate nucleus in vivo and (2) an increase in stereotyped behavior compared to the chronic saline animals. These results suggest that an increase in dopamine release from the caudate may contribute to amphetamine-induced behavioral sensitization.


Asunto(s)
Conducta Animal/efectos de los fármacos , Núcleo Caudado/metabolismo , Dextroanfetamina/farmacología , Dopamina/metabolismo , Animales , Núcleo Caudado/efectos de los fármacos , Diálisis , Masculino , Ratas , Ratas Endogámicas , Conducta Estereotipada/efectos de los fármacos , Estimulación Química
20.
Eur J Pharmacol ; 401(3): 357-63, 2000 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-10936494

RESUMEN

The ability of a physiological dose of estrogen (estradiol benzoate, estrogen: 10 microgram 48 and 24 h prior) to modulate autoreceptor-mediated changes in dopamine transport properties was investigated in a synaptosomal preparation prepared from the nucleus accumbens of ovariectomized rats. Quinpirole (1-100 microM)-mediated potentiation of [3H]dopamine uptake was attenuated in synaptosomes from estrogen-primed animals. Haloperidol (10 microM) inhibited basal uptake and effectively prevented quinpirole potentiation of uptake in both ovariectomized and estrogen-primed samples. The ability of selective protein phosphatase inhibitors to modulate autoreceptor-mediated potentiation of dopamine uptake was also examined. Pretreatment with protein phosphatase 2B (deltamethrin, cypermethrin) or protein phosphatase 1 (tautomycin) inhibitors attenuated basal and quinpirole-potentiated dopamine uptake in ovariectomized but not estrogen-primed tissue. These data suggest that autoreceptor-mediated activation of dopamine transport can be regulated by physiological doses of estrogen and implicate a role for protein phosphorylation in autoreceptor-mediated potentiation of dopamine uptake.


Asunto(s)
Autorreceptores/fisiología , Dopamina/farmacocinética , Estrógenos/farmacología , Piranos , Compuestos de Espiro , Animales , Antifúngicos/farmacología , Benzazepinas/farmacología , Transporte Biológico/efectos de los fármacos , Agonistas de Dopamina/farmacología , Antagonistas de Dopamina/farmacología , Antagonistas de los Receptores de Dopamina D2 , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Femenino , Haloperidol/farmacología , Cinética , Ovariectomía , Fosfoproteínas Fosfatasas/antagonistas & inhibidores , Proteína Fosfatasa 1 , Quinpirol/farmacología , Ratas , Ratas Sprague-Dawley , Receptores de Dopamina D1/antagonistas & inhibidores , Sinaptosomas/efectos de los fármacos , Sinaptosomas/metabolismo , Factores de Tiempo
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA