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1.
Eur. j. anat ; 22(2): 135-144, mar. 2018. graf, ilus
Artigo em Inglês | IBECS | ID: ibc-172188

RESUMO

Delayed wound healing (the diabetic ulcer) is one of the major complications of diabetes mellitus (DM), which has shown an increasing trend over previous decades to affect almost 15% of diabetic patients. Virgin coconut oil (VCO) is a natural oil rich in vitamins and antioxidants and possesses antimicrobial and antiviral activities. In the current study, we evaluated the effects of topical application of VCO on wound healing in diabetes-induced Sprague-Dawley rats. A total of 72 animals were divided into 4 groups: i.e. (I) non-diabetic nontreated (NN), (II) diabetic non-treated (DN), (III) diabetic treated with VCO (VCO), and (IV) diabetic treated with silver sulfadiazine cream (SS). Wounds were inflicted on all groups using punch biopsy needles, and the animals were treated for 14 days. Wound closure rate (WCR) was measured on day 5, 10, and 14. Histological analysis was performed on day 7 and 14. Total protein content and superoxide dismutase (SOD) activity were measured on day 1, 7, and 14. WCR in VCO group was higher on all days compared to DN. Histological analysis revealed that VCO promoted re-epithelialization and increased collagen content of wound tissue. Total protein content in VCO group was higher on day 7 and 14 compared to both DN and SS groups. VCO showed insignificant effects on SOD levels. In summary, VCO was found to be better than silver sulfadiazine cream in the healing of diabetic wounds via promoting reepithelialization and collagen synthesize as well as increasing WCR and total protein content


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Assuntos
Animais , Ratos , Óleo de Palmeira/métodos , Cicatrização , Ferimentos e Lesões/terapia , Ferimentos e Lesões/veterinária , Úlcera do Pé/patologia , Pé Diabético/terapia , Glicemia/análise , Ferimentos e Lesões/diagnóstico , Ferimentos e Lesões/patologia , Ratos Sprague-Dawley/anatomia & histologia , Ratos Sprague-Dawley/metabolismo , Sulfadiazina de Prata/uso terapêutico , Superóxido Dismutase/análise
2.
Holist Nurs Pract ; 31(3): 193-203, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28406873

RESUMO

As the use of herbal medications continues to increase in America, the potential interaction between herbal and prescription medications necessitates the discovery of their mechanisms of action. The purpose of this study was to investigate the anxiolytic and antidepressant effects of curcumin, a compound from turmeric (Curcuma longa), and its effects on the benzodiazepine site of the γ-aminobutyric acid receptor A (GABAA) receptor. Utilizing a prospective, between-subjects group design, 55 male Sprague-Dawley rats were randomly assigned to 1 of the 5 intraperitoneally injected treatment groups: vehicle, curcumin, curcumin + flumazenil, midazolam, and midazolam + curcumin. Behavioral testing was performed using the elevated plus maze, open field test, and forced swim test. A 2-tailed multivariate analysis of variance and least significant difference post hoc tests were used for data analysis. In our models, curcumin did not demonstrate anxiolytic effects or changes in behavioral despair. An interaction of curcumin at the benzodiazepine site of the GABAA receptor was also not observed. Additional studies are recommended that examine the anxiolytic and antidepressant effects of curcumin through alternate dosing regimens, modulation of other subunits on the GABAA receptor, and interactions with other central nervous system neurotransmitter systems.


Assuntos
Ansiolíticos/farmacologia , Antidepressivos/farmacologia , Curcumina/uso terapêutico , Medicina Herbária/normas , Animais , Ansiolíticos/uso terapêutico , Antidepressivos/uso terapêutico , Ansiedade/tratamento farmacológico , Curcuma , Curcumina/farmacologia , Depressão/tratamento farmacológico , Dimetil Sulfóxido/farmacologia , Dimetil Sulfóxido/uso terapêutico , Flumazenil/farmacologia , Flumazenil/uso terapêutico , Medicina Herbária/métodos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Midazolam/farmacologia , Midazolam/uso terapêutico , Modelos Animais , Estudos Prospectivos , Ratos , Ratos Sprague-Dawley/metabolismo , Natação/normas
3.
Mol Biol Rep ; 39(3): 2921-35, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21687973

RESUMO

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a neuropeptide that exerts pleiotropic functions, acting as a hypophysiotropic factor, a neurotrophic and a neuroprotective agent. The molecular pathways activated by PACAP to exert its physiological roles in brain are incompletely understood. In this study, adrenocorticotropic hormone (ACTH), prolactin, luteinising hormone (LH), follicle-stimulating hormone (FSH), thyroid-stimulating hormone (TSH), brain-derived neurotrophic factor and corticosterone blood levels were determined before and 20, 40, 60, and 120 min after PACAP intracerebroventricular administration. PACAP treatment increased ACTH, corticosterone, LH and FSH blood concentrations, while it decreased TSH levels. A proteomics investigation was carried out in hypothalamus, hippocampus and pre-frontal/frontal cortex (P/FC) using 2-dimensional gel electrophoresis at 120 min, the end-point suggested by studies on PACAP hypophysiotropic activities. Spots showing statistically significant alterations after PACAP treatment were identified by Matrix-assisted laser desorption/ionization-Time of flight mass spectrometry. Identified proteins were consistent with PACAP involvement in different molecular processes in brain. Altered expression levels were observed for proteins involved in cytoskeleton modulation and synaptic plasticity: actin in the hypothalamus; stathmin, dynamin, profilin and cofilin in hippocampus; synapsin in P/FC. Proteins involved in cellular differentiation were also modulated: glutathione-S-transferase α and peroxiredoxin in hippocampus; nucleoside diphosphate kinase in P/FC. Alterations were detected in proteins involved in neuroprotection, neurodegeneration and apoptosis: ubiquitin carboxyl-terminal hydrolase isozyme L1 and heat shock protein 90-ß in hypothalamus; α-synuclein in hippocampus; glyceraldehyde-3-phosphate dehydrogenase and prohibitin in P/FC. This proteomics study identified new proteins involved in molecular mechanisms mediating PACAP functions in the central nervous system.


Assuntos
Lobo Frontal/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Hipocampo/metabolismo , Hipotálamo/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/farmacologia , Ratos Sprague-Dawley/genética , Hormônio Adrenocorticotrópico/sangue , Análise de Variância , Animais , Fator Neurotrófico Derivado do Encéfalo/sangue , Corticosterona/sangue , Eletroforese em Gel Bidimensional , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Masculino , Prolactina/sangue , Proteômica/métodos , Ratos , Ratos Sprague-Dawley/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Tireotropina/sangue , Fatores de Tempo
4.
Am J Physiol Regul Integr Comp Physiol ; 298(1): R70-8, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19889867

RESUMO

The present study was conducted to quantify in vitro gonadotropin-releasing hormone (GnRH) release parameters in the male marmoset. We established primary cultures of marmoset hypothalamic tissues for approximately 2 days (marmosets) to assess GnRH release profiles in vitro in hypothalamic explants from testis-intact and gonadectomized males. Pulsatile GnRH release profiles were readily demonstrated from in vitro hypothalamic explants isolated from adult male marmoset monkeys. Gonadectomy of male marmosets resulted in elevated mean GnRH and pulse amplitude from hypothalamic explants on the 1st day of culture (day 0). GnRH pulse amplitude increased by day 2 in approximately 67% of hypothalamic explants from testis-intact marmosets, suggesting release from an endogenous regulator of GnRH. We also measured GnRH release profiles in vitro in hypothalamic explants from testis-intact and gonadectomized rats. Male rats showed no changes in any concentration or frequency release parameters for GnRH following gonadectomy or during successive days in culture. The present study represents a unique examination of GnRH release from male marmoset monkey hypothalamic tissue and compares release dynamics directly with those obtained from male rat, suggesting a species difference in feedback regulation of GnRH release.


Assuntos
Callithrix/metabolismo , Hormônio Liberador de Gonadotropina/metabolismo , Hipotálamo/metabolismo , Ratos Sprague-Dawley/metabolismo , Animais , Retroalimentação Fisiológica/fisiologia , Hipotálamo/efeitos dos fármacos , Masculino , Orquiectomia , Ocitócicos/farmacologia , Ocitocina/farmacologia , Cloreto de Potássio/farmacologia , Ratos , Especificidade da Espécie , Testículo/fisiologia
5.
Planta Med ; 74(15): 1832-6, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19009500

RESUMO

A sensitive and rapid liquid chromatography-mass spectrometric method for the determination of ophiopogonin D in rat plasma was developed and validated. Chromatographic separation was performed on a C (18) column using a step gradient program with the mobile phase of 0.5 mmol/L ammonium chloride solution and acetonitrile. Ophiopogonin D was quantified using an electrospray negative ionization mass spectrometry in the selected ion monitoring (SIM) mode using digoxin as an internal standard. Good linearity was obtained in the concentration range of 2.5 - 480.0 ng/mL ( R2 = 0.9984). The lower limit of quantification (LLOQ) and lower limit of detection (LLOD) were 2.5 ng/mL and 1.0 ng/mL, respectively. Both the intra- and inter-day precision was less than 8.9 % and the accuracy was within 97.5 - 107.3 %. The pharmacokinetic study of ophiopogonin D in rats was then defined using the method after intravenous dosing (77.0 microg/kg). The plasma concentration-time profile for ophiopogonin D was best fitted to an open two-compartment model with a clearance of 0.024 +/- 0.010 L/min/kg and a terminal half life of 17.29 +/- 1.70 min. A comparison of the pharmacokinetics of ophiopogonin D as a pure compound and as a component of 'SHENMAI' injection revealed a significantly smaller clearance of ophiopogonin D (0.007 +/- 0.002 L/min/kg) for the latter formulation, consistent with an inhibition by one or more other components in the formulation.


Assuntos
Ophiopogon , Saponinas/farmacocinética , Espirostanos/farmacocinética , Animais , Cromatografia Líquida/métodos , Ratos , Ratos Sprague-Dawley/metabolismo , Saponinas/sangue , Saponinas/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espirostanos/sangue , Espirostanos/química
6.
Horiz. méd. (Impresa) ; 6(1): 29-35, jun. 2006. tab
Artigo em Espanhol | LILACS, LIPECS | ID: lil-677722

RESUMO

La harina tostada de cañihua (Chenopodium pallidicaule Aellen), conocida como cañihuaco, está asociada popularmente como una alternativa terapéutica a problemas de hipercolesterolemia. En el presente estudio se evaluaron durante 60 días 22 ratas albinas macho cepa Sprague dawley de 21 días de nacidas, destetadas, procedentes del CENAN (Centro Experimental Nacional en Alimentación y Nutrición), las cuales fueron distribuidas al azar en cuatro grupos. (a) Consumieron dieta control con caseína, (b) Consumieron dieta control con caseína por 30 días y con dieta cañihuaco por otros 30 días, (c) Consumieron dieta hipergrasa con manteca de palma por 30 días y dieta control con caseína por 30 días más, (d) Consumieron dieta hipergrasa por 30 días y dieta cañihuaco por otros 30 días más. Al inicio se les tomó análisis basal de colesterol total y fraccionado LDL-C, HDL-C, VLDL-C y triglicéridos, repitiéndose a los 30 días y a los 60 días. Concluyéndose que el consumo de dieta cañihuaco en ratas que recibieron dieta hipergrasa tienen una probabilidad de que se incremente los niveles de HDL-C con el consumo de dieta cañihuaco de cinco veces mayor que si se consume dieta caseína. Asimismo, fue evidente el incremento de HDL-C en las ratas que consumieron dieta a base de cañihuaco.


Roasted Cañihua (Chenopodium pallidicaule AelIen) flour (Chenopodium pallidicaule AelIen), a.k.a. cañihuaco, is popularly used as an alternative treatment for hypercholesterolemia. In the present study, 22 weaned male albino Sprague Dawley rats, 21 days old coming from CENAN were distributed randomly in four groups and evaluated during 60 days. Rats from group (a) consumed control diet with casein, group (b) consumed control diet with casein for 30 days followed by cañihuaco diet for another 30 days. On group (c) they consumed a hyper greasy diet with palm butter for 30 days and control diet with case in for an extra 30 days and group (d) consumed hyper greasy diet for 30 days followed by cañihuaco diet for another 30 days. At the beginning of the experiment, basal analysis was taken to check total cholesterol and fractionated LDL-C, HDL-C, VLDL-C and triglycerides, repeating the same tests after 30 and 60 days. From the results we can conclude that cañihuaco consumption on the diet of rats receiving the hyper greasy die has the probability of increasing HDL-C levels up to five times compared to the casein diet. Also, the increase of HDL-C levels on rats under the cañihuaco diet was evident.


Assuntos
Masculino , Animais , Ratos , Chenopodium , Fitoterapia , Farinha , Hipercolesterolemia/terapia , Plantas Medicinais , Ratos Sprague-Dawley/metabolismo , Fenômenos Químicos
7.
Horiz. méd. (Impresa) ; 6(1): 45-52, jun. 2006. ilus, tab, graf
Artigo em Espanhol | LILACS, LIPECS | ID: lil-677724

RESUMO

Se evaluó el efecto tóxico agudo del aceite de Plukenetia volúbilis (Sacha Inchi), determinando la Dosis Letal -50 (DL50) en 42 ratones de la cepa Nish, distribuidos en siete grupos de seis ratones cada uno, a los cuales se les administró, vía oral, dosis crecientes del aceite. Para evaluar el efecto hipolipemiante utilizamos 55 ratas albinas machos de la raza Holtzman, con un peso entre 194 g y 290 g y dos meses de edad. Se utilizó una dieta con 15 por ciento de grasas saturadas para elevar los lípidos séricos durante todo el tiempo del experimento. Utilizamos tres dosis diferentes de aceite de Sacha Inti, administradas durante 14 días consecutivos, comparando sus efectos con un control positivo (Lovastatina) y un control negativo (SF). Se controló el peso de los animales y los valores de colesterol, HDL y triglicéridos sanguíneos en tres tiempos diferentes. El análisis estadístico se realizó mediante el programa STATA 8.2. La DL50 fue de 111,65 mg/kg; hubo una reducción significativa de los valores sanguíneos de triglicéridos y LDL, mas no de colesterol y peso de los animales.


The acute toxic of Plukenetia volúbilis (Sacha Inchi) oil was evaluated. We calculated the Medial Lethal Dose (DL50) on 42 mice of the Nish strain, distributed in seven groups of six mice each, to whom a different and increasing dose was administered by oral route. To determine the hypolipidemic effect, we used 55 male albino rats of the Holtzman breed, whose weight fluctuateed between 194 and 290 g. The animals were fed with 15% of a saturateed fat diet for 14 days to produce hyperlipidemia during the whole period of the experiment. Treatment with Sacha Inchi oil in three different doses during 14 consecutive days was compared to the effects of a positive (lovastatine) and a negative control (physiological serum). The weight, cholesterol, HDL, LDL, VLDL, and triglycerides, were controlled in three different periods of time. Statistics analysis was made using the STATA 8.2 program. The DL50 was detrmined at 111,65 mg/Kg and the level of tryclicerides and LDL were statistically reduced, but not the cholesterol values or the animals' weight.


Assuntos
Masculino , Animais , Camundongos , Ratos , Óleos de Plantas/toxicidade , Dose Letal Mediana , Euphorbiaceae/toxicidade , Plantas Medicinais/toxicidade , Ratos Sprague-Dawley/metabolismo , Testes de Toxicidade Aguda
8.
J Comp Neurol ; 448(3): 217-29, 2002 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12115705

RESUMO

Two isoforms of the vesicular glutamate transporter, VGLUT1 and VGLUT2, were recently cloned and biophysically characterized. Both VGLUT1 and VGLUT2 specifically transport glutamate into synaptic vesicles, making them definitive markers for neurons using glutamate as a neurotransmitter. The present study takes advantage of the specificity of the vesicular transporters to afford the first detailed map of putative glutamatergic neurons in the rat hypothalamus. In situ hybridization analysis was used to map hypothalamic distributions of VGLUT1 and VGLUT2 mRNAs. VGLUT2 is clearly the predominant vesicular transporter mRNA found in the hypothalamus; rich expression can be documented in regions regulating energy balance (ventromedial hypothalamus), neuroendocrine function (preoptic nuclei), autonomic tone (posterior hypothalamus), and behavioral/homeostatic integration (lateral hypothalamus, mammillary nuclei). Expression of VGLUT1 is decidedly more circumspect and is confined to relatively weak labeling in lateral hypothalamic regions, neuroendocrine nuclei, and the suprachiasmatic nucleus. Importantly, dual-label analysis revealed no incidence of colocalization of VGLUT1 or VGLUT2 mRNAs in glutamic acid decarboxylase (GAD) 65-positive neurons, indicating that GABA neurons do not express either transporter. Our data support a major role for hypothalamic glutamatergic neurons in regulation of all aspects of hypothalamic function.


Assuntos
Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Ácido Glutâmico/metabolismo , Hipotálamo/metabolismo , Proteínas de Membrana Transportadoras , Neurônios/metabolismo , Ratos Sprague-Dawley/metabolismo , Transmissão Sináptica/fisiologia , Proteínas de Transporte Vesicular , Animais , Biomarcadores/análise , Regulação da Expressão Gênica/fisiologia , Glutamato Descarboxilase/genética , Hipotálamo/citologia , Hibridização In Situ , Masculino , Neurônios/citologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley/anatomia & histologia , Vesículas Sinápticas/metabolismo , Proteína Vesicular 1 de Transporte de Glutamato , Proteína Vesicular 2 de Transporte de Glutamato
9.
West Indian med. j ; West Indian med. j;50(suppl 7): 34, Dec. 2001.
Artigo em Inglês | MedCarib | ID: med-60

RESUMO

Water extracts from the fruit of the coraili plant, Mormordica charantia, have been reported to have hypoglycaemic effect. The fruit of this plant is eaten as a vegetable by man. Significant lowering of blood glucose levels has been observed following the oral administration of coraili fruit extracts. However, some authors have shown that there are no beneficial hypoglycaemic effect from fruit extracts. In this experiment, water extract of the entire coraili fruit was administered orally to alloxan-diabetic Sprague Dawley Rats ad libitum for 7 hours. The rats were placed on normal diet during the experiment. Results showed that 7 hours after the administration of this extract, blood glucose levels dropped significantly. It was also observed that, 7 hours after the discontinuation of the administration of the extract in alloxan-diabetic rats, blood glucose levels rose close to the pre-administration levels. The implications of these findings will be discussed. (AU)


Assuntos
21003 , Ratos , Plantas/uso terapêutico , Glicemia/análise , Diabetes Mellitus/dietoterapia , Ratos Sprague-Dawley/metabolismo
10.
Neurosci Lett ; 307(1): 57-60, 2001 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-11516574

RESUMO

In male Sprague-Dawley rats intraperitoneal (i.p.) injection of Escherichia coli lipopolysaccharide (0.25, 0.50 and 1 mg/kg) increased anxiety levels. This effect was reversed by a prior, concomitant, and subsequent i.p. treatment with melatonin (4 and 6 mg/kg). As the effects of melatonin upon the actions induced by lipopolysaccharide were reversed by the melatonin receptor antagonist luzindole (30 and 60 mg/kg, i.p.), we argued that they are, but not only, melatonin receptor mediated. These findings, in accordance with our previous works, suggest that melatonin could be useful in the treatment of sickness behaviour associated with systemic infection diseases or as adjuvant in the anti-anxiety therapy.


Assuntos
Ansiedade/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Interações Medicamentosas/fisiologia , Lipopolissacarídeos/farmacologia , Melatonina/farmacologia , Ratos Sprague-Dawley/psicologia , Receptores de Superfície Celular/agonistas , Receptores Citoplasmáticos e Nucleares/agonistas , Animais , Ansiedade/induzido quimicamente , Ansiedade/fisiopatologia , Infecções Bacterianas/complicações , Infecções Bacterianas/metabolismo , Infecções Bacterianas/fisiopatologia , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Encéfalo/metabolismo , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Relação Dose-Resposta a Droga , Endotoxinas/efeitos adversos , Endotoxinas/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Melatonina/metabolismo , Ratos , Ratos Sprague-Dawley/metabolismo , Receptores de Superfície Celular/antagonistas & inibidores , Receptores de Superfície Celular/metabolismo , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores de Melatonina , Triptaminas/farmacologia
11.
J Comp Neurol ; 427(1): 139-49, 2000 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-11042596

RESUMO

Manipulation of cortical serotonin (5-HT) levels in perinatal rodents produces significant alterations in the development of the layer IV cortical representation of the mystacial vibrissae. Monoamine oxidase A (MAO(A)) knockout mice have highly elevated cortical 5-HT and completely lack barrels in somatosensory cortex (S-I). The present study was undertaken to determine whether the effects on thalamocortical development seen in MAO(A) knockout mice can be replicated in perinatal rats treated with an MAO(A) inhibitor and, second, to determine whether these effects persist with continued treatment or after discontinuation of the drug. Littermates were injected with either clorgyline (5 mg/kg) or sterile saline five times daily. Clorgyline administration from birth to postnatal day (P) 6, 8, or 10 produced increases of 1,589.4 +/- 53.3%, 1660.2 +/- 43.1% and 1,700.5 +/- 84.5 %, respectively, in cortical 5-HT as compared with controls. Serotonin immunocytochemistry, 1,1;-dioctadecyl-3,3,3", 3;-tetramethylindocarbocyanine perchlorate (DiI) labeling of thalamocortical afferents and Nissl and cytochrome oxidase staining of layer IV cellular aggregates demonstrated that clorgyline treatment from P0 to P6 produced a complete absence of any segmentation of vibrissae-related patches in S-I. However, continued treatment until P8 or P10 did not prevent the appearance of these patches. Animals treated with clorgyline from birth to P6 and killed on P8 or P10 had increases of 546.8 +/- 33.2% and 268.8 +/- 6.3% in cortical 5-HT and they had qualitatively normal vibrissae-related patterns in S-I. These results indicate that clorgyline treatment produces a transient disruption of vibrissae-related patterns, despite the continued presence of elevated cortical 5-HT.


Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Padronização Corporal/efeitos dos fármacos , Clorgilina/farmacologia , Ratos Sprague-Dawley/crescimento & desenvolvimento , Serotonina/metabolismo , Córtex Somatossensorial/crescimento & desenvolvimento , Vibrissas/crescimento & desenvolvimento , Fatores Etários , Animais , Animais Recém-Nascidos/anatomia & histologia , Animais Recém-Nascidos/metabolismo , Padronização Corporal/fisiologia , Esquema de Medicação , Feminino , Masculino , Mecanorreceptores/citologia , Mecanorreceptores/efeitos dos fármacos , Mecanorreceptores/crescimento & desenvolvimento , Mecanorreceptores/metabolismo , Vias Neurais/citologia , Vias Neurais/efeitos dos fármacos , Vias Neurais/crescimento & desenvolvimento , Vias Neurais/metabolismo , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/fisiologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley/anatomia & histologia , Ratos Sprague-Dawley/metabolismo , Córtex Somatossensorial/citologia , Córtex Somatossensorial/efeitos dos fármacos , Córtex Somatossensorial/metabolismo , Tálamo/citologia , Tálamo/efeitos dos fármacos , Tálamo/crescimento & desenvolvimento , Tálamo/metabolismo , Vibrissas/citologia , Vibrissas/efeitos dos fármacos , Vibrissas/inervação
12.
Toxicol Appl Pharmacol ; 142(1): 133-42, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9007042

RESUMO

Chronic administration of thiazopyr in the diet at dose levels of 1000 and 3000 ppm, but not 100 ppm, has demonstrated an increase in thyroid follicular cell tumors in male Sprague-Dawley rats. In the studies reported here we have evaluated the mechanism of thiazopyr-induced thyroid tumors by studying the effect of thiazopyr on a number of endpoints that indicate hypothalamic-pituitary-thyroid homeostasis. At a dose level of 3000 ppm, thiazopyr caused a marked depression in circulating levels of T4 as soon as 7 days after commencement of treatment. Concurrent with this decrease in T4 was an increase in TSH levels, an increase in thyroid and liver weights, a three- to sixfold increase in hepatic T4-uridine diphosphate glucuronosyl transferase (UDPGT) activity, and increases in thyroid follicular cell hypertrophy and hyperplasia. Dose-related changes associated with thiazopyr treatment were significant increases in liver weight, thyroid weight, and hepatic T4-UDPGT activity at high doses. Increased levels of serum TSH, T3, and rT3, decreased levels of T4, and an increased incidence of thyroid follicular cell hypertrophy and hyperplasia were observed 56 days after the initiation of 3000 ppm thiazopyr. All the changes, except thyroid weight, were partially or completely reversible upon removal of thiazopyr from the diet. Increased thyroid T4 elimination, primarily via increased hepatic conjugation by T4-UDPGT, resulting in decreased serum T4, appeared to be responsible for the increased TSH levels. The sustained increase in TSH by thiazopyr appears responsible for the stimulation of the thyroid follicular cells resulting in follicular cell hypertrophy, hyperplasia, and ultimately neoplasia. In summary, evidence is presented for a hormonally mediated, threshold-dependent process for the development of thyroid follicular cell tumors from high-dose thiazopyr administration in male rats. This mechanism is not considered to be relevant to humans, since the thyroid of humans is much less sensitive to this pathogenic phenomenon than rodents.


Assuntos
Adenoma/induzido quimicamente , Glucuronosiltransferase/biossíntese , Fígado/efeitos dos fármacos , Niacina/análogos & derivados , Adeno-Hipófise/metabolismo , Ratos Sprague-Dawley/metabolismo , Tiazóis/toxicidade , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/induzido quimicamente , Tireotropina/metabolismo , Tiroxina/deficiência , Tri-Iodotironina/metabolismo , Adenoma/metabolismo , Animais , Bile/metabolismo , Dieta , Relação Dose-Resposta a Droga , Indução Enzimática/efeitos dos fármacos , Glucuronosiltransferase/genética , Homeostase/efeitos dos fármacos , Hiperplasia , Hipertrofia , Iodeto Peroxidase/biossíntese , Iodeto Peroxidase/genética , Iodo/metabolismo , Fígado/enzimologia , Fígado/patologia , Masculino , Niacina/farmacologia , Niacina/toxicidade , Tamanho do Órgão/efeitos dos fármacos , Ratos , Caracteres Sexuais , Especificidade da Espécie , Tiazóis/farmacologia , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/metabolismo , Tiroxina/metabolismo
13.
J Anim Sci ; 74(7): 1657-63, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8818812

RESUMO

One hundred twenty male Sprague-Dawley rats, averaging 108.6 g initial body weight, were used in two feeding experiments to evaluate the utilization of Cu in Cu proteinate, Cu lysine, and cupric sulfate. In Exp. 1, 60 rats were randomly assigned to 12 treatments in a 2 x 2 x 3 factorial arrangement of treatments, with Zn supplementation at 0 or 1000 mg/kg diet, Cu supplementation at 5 or 15 mg/kg diet, and Cu form of CuSO4.5H2O, Cu proteinate, or Cu lysine. The purified basal diet contained .81 mg Cu, 20 mg Zn, and 60 mg Fe/kg diet. Experiment 2 was similar to Exp. 1 except Zn was replaced by Fe. In Exp. 1, feed intake of Cu proteinate (15.74 g/d) and Cu lysine (15.74 g/d) treatments was higher (P < .05) than that of CuSO4 (15.33 g/d). Body weight gain and feed intake were increased by high dietary Cu at either requirement or high levels of dietary Zn (P < .05). There were no differences in feed intake or body weight gain among the treatment groups in Exp. 2 (P > .05). The Cu utilization of Cu proteinate and Cu lysine were higher (P < .05) based on the liver Cu content. The rats fed Cu complexes had a higher liver Fe or Zn content (P < .05) than the rats fed CuSO4, suggesting that Cu complexes are absorbed via another mechanism that differs from that of inorganic Cu and does not interfere with Zn and Fe. Spleen Cu content may be a sensitive indicator of Cu status. High dietary Zn decreased Cu utilization, but this effect was overcome by high dietary Cu.


Assuntos
Sulfato de Cobre/farmacologia , Cobre/metabolismo , Cobre/farmacologia , Lisina/farmacologia , Ratos Sprague-Dawley/metabolismo , Animais , Cobre/análise , Ingestão de Alimentos/fisiologia , Alimentos Fortificados , Ferro/análise , Ferro/farmacologia , Rim/química , Fígado/química , Pulmão/química , Masculino , Modelos Biológicos , Miocárdio/química , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley/fisiologia , Baço/química , Aumento de Peso/fisiologia , Zinco/análise , Zinco/farmacologia
14.
J Comp Neurol ; 363(2): 264-80, 1995 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-8642074

RESUMO

Dopamine afferents to the cortex regulate the excitability of pyramidal neurons via a direct synaptic input. However, it has not been established whether dopamine also modulates pyramidal cell activity indirectly through synapses on gamma-aminobutyric acid (GABA) interneurons, and whether such inputs differ across cortical regions and species. We sought to address these issues by an immunocytochemical electron microscopic approach that combined peroxidase staining for dopamine or tyrosine hydroxylase (TH) with a pre-embedding gold-silver marker for GABA. In the deep layers of the rat prefrontal cortex and in the superficial layers of the monkey prefrontal and primary motor cortices, terminal varicosities immunoreactive for dopamine or TH formed primarily thin, symmetric synapses on distal dendrites. Both GABA-immunoreactive dendrites as well as unlabeled spines and dendrites were contacted by dopamine- or TH-immunoreactive terminals. Synaptic specializations were detected at some, but not all of these contacts. The relative frequency of these appositional and synaptic contacts did not appear to differ between the rat and monkey prefrontal cortex, or between the monkey prefrontal and motor cortices. Across regions and species, labeled and unlabeled targets of dopamine- or TH-positive terminals received additional synaptic input from unlabeled, and occasionally GABA-immunoreactive terminals. Close appositions between dopamine- or TH-immunoreactive and GABA-positive terminals were observed only rarely. These findings indicate that dopamine afferents provide direct synaptic inputs to GABA local circuit neurons in a consistent fashion across cortical regions and species. Thus, dopamine's cellular actions involve direct as well as modulatory effects on both GABA interneurons and pyramidal projection neurons.


Assuntos
Axônios/química , Dendritos/química , Macaca fascicularis/metabolismo , Terminações Nervosas/química , Ratos Sprague-Dawley/metabolismo , Sinapses/química , Animais , Axônios/ultraestrutura , Dendritos/ultraestrutura , Dopamina/análise , Técnicas Imunoenzimáticas , Interneurônios/química , Interneurônios/ultraestrutura , Macaca fascicularis/anatomia & histologia , Masculino , Microscopia Imunoeletrônica , Córtex Motor/química , Terminações Nervosas/ultraestrutura , Córtex Pré-Frontal/química , Ratos , Ratos Sprague-Dawley/anatomia & histologia , Sinapses/enzimologia , Tirosina 3-Mono-Oxigenase/análise , Ácido gama-Aminobutírico/análise
15.
J Biochem ; 116(3): 677-81, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7852290

RESUMO

Rat and mouse cDNAs for Zn-alpha 2-glycoprotein (Zn alpha 2gp) were isolated from liver libraries (lambda gt11) and compared with the human one. The lengths of cDNA inserts analyzed were 1,233 and 1,273 nucleotides for rat and mouse, respectively. The deduced amino acid sequences suggested that rat and mouse Zn alpha 2gp proteins consist of 279 and 290 amino acid residues in the mature form, respectively. They have 59.4% (rat) and 58.6% (mouse) identities in amino acid sequence with the human counterpart, and between rat and mouse the identity is 88.5%. Among the three domains, domain B is best conserved; the identities are 74.7, 73.6, and 95.6% between human and rat, human and mouse, and rat and mouse, respectively. Four cysteine and eight tryptophan residues are all conserved, and two of the three asparagine residues that carry a glycan in the human protein are conserved. Analysis of rat tissues by Northern blot suggested that its mRNA is expressed in liver, and, to a much lesser extent in submandibular gland, lung, kidney, and stomach. A more detailed study by in situ hybridization demonstrated that some epithelial cells of renal tubules and the isthmus and the neck zone cells of gastric fundic glands express Zn alpha 2gp mRNA.


Assuntos
DNA Complementar/isolamento & purificação , Glicoproteínas/genética , Fígado/metabolismo , Camundongos Endogâmicos BALB C/metabolismo , RNA Mensageiro/biossíntese , Ratos Sprague-Dawley/metabolismo , Proteínas de Plasma Seminal , Animais , Sequência de Bases , Código Genético , Biblioteca Genômica , Humanos , Camundongos , Dados de Sequência Molecular , Ratos , Ratos Wistar , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Especificidade da Espécie , Relação Estrutura-Atividade , Glicoproteína Zn-alfa-2
16.
Cell Mol Neurobiol ; 12(5): 447-54, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1468115

RESUMO

1. A luteinizing hormone-releasing hormone (LHRH)-like molecule produced by thymocytes is similar to hypothalamic LHRH in both bioactivity and antigenicity. 2. We determined whether this thymic LHRH is identical to or only homologous with hypothalamic LHRH by synthesizing and sequencing the cDNA of rat thymus LHRH. 3. The thymocyte and hypothalamic LHRH cDNAs are identical, indicating, that the amino acid sequences of LHRH produced in the hypothalamus and the immune system are also identical. 4. This is the first report showing conclusively that cell of the immune system transcribe the authentic mRNA for a hypothalamic releasing factor, LHRH.


Assuntos
Hormônio Liberador de Gonadotropina/genética , RNA Mensageiro/biossíntese , Linfócitos T/metabolismo , Timo/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA/genética , Feminino , Hipotálamo/química , Dados de Sequência Molecular , Hipófise/química , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley/crescimento & desenvolvimento , Ratos Sprague-Dawley/metabolismo , Homologia de Sequência do Ácido Nucleico , Timo/citologia
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