Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 158
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Endocrinol Invest ; 44(3): 391-402, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32691371

RESUMEN

BACKGROUND: Testicular adrenal rest tumors (TARTs) are benign masses deemed to originate from pluripotent testicular steroidogenic cells that grow under chronic ACTH stimulation. These lesions, occasionally misdiagnosed as Leydig cell tumors (LCTs), are typically described in patients with congenital adrenal hyperplasia (CAH). X-linked adrenoleukodystrophy (X-ALD) is an inherited disorder of beta-oxidation with accumulation of very long chain fatty acids (VLCFAs) in various tissues, and a rare cause of primary adrenal insufficiency (PAI). TARTs have never been associated with X-ALD. CASE 1 DESCRIPTION: A 19-year old male, who had previously undergone bilateral enucleation of presumed LCTs, was referred to our unit. Follow-up scans showed persistent bilateral lesions compatible with TARTs. Biochemical exams revealed PAI but excluded CAH. A serum VLCFAs panel was consistent with X-ALD, with gene testing confirming the diagnosis. Histological revision of the previously resected testicular lesions was compatible with TARTs. Start of glucocorticoid replacement therapy was associated with a reduction of testicular masses. CASE 2 DESCRIPTION: A 26-year old X-ALD male was diagnosed with bilateral testicular lesions compatible with TARTs. These lesions increased after ACTH elevation following switch to modified-release hydrocortisone. Clinical and sonographic findings allowed for a "watchful-waiting" approach, avoiding unnecessary surgery. CONCLUSION: These are the first cases reported of TARTs in patients with X-ALD-associated PAI. Testicular lesions in patients with an early onset of ACTH elevation, regardless of the cause, should always be thoughtfully investigated, as they may reveal themselves as TARTs. We suggest that all patients affected from chronic ACTH elevation of a young age of onset should undergo testicular ultrasound in order to evaluate the presence of these lesions. GRT in these patients might also help preserving fertility.


Asunto(s)
Hiperplasia Suprarrenal Congénita/diagnóstico , Tumor de Resto Suprarrenal/diagnóstico , Adrenoleucodistrofia/diagnóstico , Insuficiencia Corticosuprarrenal Familiar/diagnóstico , Neoplasias Testiculares/diagnóstico , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Pronóstico , Adulto Joven
2.
Pharmacol Res ; 91: 36-46, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25434589

RESUMEN

Peripheral neuropathy is characterized by abnormal pain responses triggered by the release of several mediators and neuronal hyperexcitability at the spinal cord level. Emerging evidence indicates that the enhanced activity of dorsal horn neurons requires communication with glia and microglia, cells that are physiologically involved in neuronal wellbeing. Prokineticins (PKs), which include PK1 and PK2, represent a novel family of chemokines characterized by a unique structural motif comprising five disulfide bonds. They are expressed in the peripheral and central nervous system. PKs bind two G protein coupled receptors, PKR1 and PKR2, and participate in the regulation of several biological processes, including pain sensation. This study aimed to investigate the anti-nociceptive effect of PC1, a non-peptide PKR1-preferring antagonist, in a mouse model of neuropathic pain. To do this, we assessed the activity of spinal cord nociceptive neurons as well as astrocyte and microglia phenotypes after repeated administration of PC1 in vivo. PC1 treatment strongly delayed the development of thermal hyperalgesia and tactile and mechanical allodynia. It also reduced spinal microglial and glial activation 8 days post injury in spared nerve injury (SNI) mice. Neuropathic mice showed an increased level of PK2 protein in the spinal cord, mostly in astrocytes. PC1 treatment completely reversed the increased responsiveness to mechanical stimuli, the decreased threshold of neuronal activation, and the increased spontaneous activity that were observed in nociceptive specific (NS) neurons of SNI mice.


Asunto(s)
Analgésicos/uso terapéutico , Hormonas Gastrointestinales/metabolismo , Neuralgia/tratamiento farmacológico , Neuropéptidos/metabolismo , Receptores Acoplados a Proteínas G/antagonistas & inhibidores , Médula Espinal/efectos de los fármacos , Triazinas/uso terapéutico , Animales , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Conducta Animal/efectos de los fármacos , Hormonas Gastrointestinales/genética , Calor , Hiperalgesia/tratamiento farmacológico , Hiperalgesia/metabolismo , Masculino , Ratones , Neuralgia/metabolismo , Neuronas/efectos de los fármacos , Neuronas/fisiología , Neuropéptidos/genética , Traumatismos de los Nervios Periféricos/tratamiento farmacológico , Traumatismos de los Nervios Periféricos/metabolismo , ARN Mensajero/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Nervio Ciático/efectos de los fármacos , Nervio Ciático/lesiones , Nervio Ciático/metabolismo , Médula Espinal/metabolismo , Médula Espinal/fisiología , Triazinas/farmacología
3.
J Pharmacol Toxicol Methods ; 106: 106911, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32805386

RESUMEN

INTRODUCTION: Clonogenic assay evaluates the potential of cells to undergo division or generate clones following treatment with a chemical or other agent, thereby allowing the evaluation of cytotoxic and/or antiproliferative effects. Clonogenic assay analysis using traditional methods tends to be time-consuming and yield inconsistent results, whereas results from analyses conducted using automated image processing methods may be misleading or subject to misinterpretation. Thus, the aim of this work was to validate and demonstrate the applicability of a recently developed software. METHODS: Repeatability of measurements was evaluated by comparing results from 10 replicate images from a single well. To evaluate the viability of the software, results were compared with those obtained from manual counting, crystal violet optical density, and up-to-date automated methods. A clonogenic index was experimentally developed using the individual area occupied by colonies, while clone stratification was used to differentiate between antiproliferative and cytotoxic effects. RESULTS: The developed software showed to be a reliable and consistent tool for clonogenic assay evaluation, presenting a repeatability mean error of 0.79% for the number of colonies and 0.89% for the total area of colonies, as well as exhibiting a significant correlation (p < 0.05) with results obtained from widely adopted gold standard methods. The software was also able to detect an appropriate dose-dependent effect as well as a predominant cytotoxic effect of vincristine on MCF-7 cells and calculate the clonogenic index. DISCUSSION: Therefore, this software is adequate for the analysis of clonogenic assay images, differentiating between cytotoxic and antiproliferative trends.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Microscopía Intravital/métodos , Programas Informáticos , Ensayo de Tumor de Célula Madre/métodos , Antineoplásicos Fitogénicos/farmacología , Recuento de Células/métodos , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales/métodos , Humanos , Células MCF-7 , Reproducibilidad de los Resultados , Vincristina/farmacología
4.
G Chir ; 30(8-9): 362-4, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19735616

RESUMEN

Mesenteric cystic lymphangioma is a rare lesion. We described a case of 20 years old patient with an asymptomatic cystic lymphangioma that was detected after ultrasound scan performed for a minor abdominal trauma. The patient was treated with laparoscopic exploration and an intestinal resection by mini-laparotomy. Although very rare, cystic mesenteric lymphangiomas may cause complications; therefore, they should be always treated with surgical excision and should be included in the differential diagnosis of acute abdomen.


Asunto(s)
Laparoscopía/métodos , Linfangioma Quístico/cirugía , Neoplasias Peritoneales/cirugía , Traumatismos Abdominales/cirugía , Adulto , Anastomosis Quirúrgica/métodos , Diagnóstico Diferencial , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Humanos , Ileus/cirugía , Hallazgos Incidentales , Linfangioma Quístico/complicaciones , Linfangioma Quístico/diagnóstico , Masculino , Quiste Mesentérico/cirugía , Neoplasias Peritoneales/complicaciones , Neoplasias Peritoneales/diagnóstico , Resultado del Tratamiento
5.
Placenta ; 29 Suppl B: 178-83, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18755508

RESUMEN

Severe forms of male-factor infertility are associated with an increased risk of testicular cancer and scrotal ultrasonography is widely used for diagnosis. In this study, 2172 male members of infertile couples referred to our Reproductive Medicine Unit were submitted to scrotal ultrasonography and 835 selected patients had been followed during a 2-year period. Eight out of nine neoplastic nodules found at the initial examination were unpalpable and discovered by ultrasonography. Ten tumoral lesions were found in 370 testicular biopsies performed for diagnostic purposes or to extract spermatozoa; and eight additional neoplastic lesions were discovered during the 2-year follow-up of 835 patients. The cumulative rate of neoplastic disease was 3.2%. Thirteen cases (1.5%) were malignant (12 germ cell tumours and one non-Hodgkin lymphoma of testicular origin); the remaining 14 were benign forms (Leydig cell tumours and hyperplasias, Sertoli cell nodules, adenomatoid tumours). Testicular volume (cut-off: 12ml) resulted weakly correlated with germ cell cancer (p=n.s., odds ratio 2.01) while low total sperm count (<40x10(6)) (p=0.002, odds ratio 8.4), previous cryptorchidism (p=0.04, odds ratio 7.5) and hypergonadotrophic hypogonadism (p=0.04, odds ratio 7.9) were associated with an increased risk. But a stronger correlation with germ cell cancer was found in the patients with some utrasonographic anomalies, i.e. testicular microlithiasis (p=0.0015, odds ratio 37.1) or larger calcifications not fitting the description of testicular microlithiasis (p<0.0001, odds ratio 69.5). Our findings indicate that scrotum ultrasonography should always be advised in subfertile men with <40x10(6) spermatozoa/ejaculate or hypergonadotrophic hypogonadism or previous cryptorchidism, and that particular care should be taken in the presence of testicular microlithiasis or testicular calcifications. These men should be aware of the existence of higher risk of testicular cancer and trained in testicular self-examination.


Asunto(s)
Infertilidad Masculina/complicaciones , Neoplasias/etiología , Adulto , Biopsia , Femenino , Neoplasias de los Genitales Masculinos/diagnóstico por imagen , Neoplasias de los Genitales Masculinos/epidemiología , Neoplasias de los Genitales Masculinos/etiología , Humanos , Infertilidad Masculina/diagnóstico por imagen , Infertilidad Masculina/epidemiología , Infertilidad Masculina/patología , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Escroto/diagnóstico por imagen , Enfermedades Testiculares/complicaciones , Enfermedades Testiculares/diagnóstico por imagen , Enfermedades Testiculares/epidemiología , Enfermedades Testiculares/patología , Ultrasonografía , Adulto Joven
6.
G Chir ; 29(4): 141-4, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18419976

RESUMEN

Castleman's disease is a rare disorder of the lymphoid tissue that usually occurs in the mediastinum even if extrathoracic involvement, including neck, axilla, mesentery and retroperitoneum, has also been described. We report a case of a 69 years old men with peripancreatic localisation, mimicking a pancreatic neoplasm treated with local excision. Only seven cases of pancreatic and peripancreatic localisation are described in the world-wide literature. This particular site of disease may give troublesome differential diagnosis due to non specific clinical signs and radiological features. Often surgical excision is both diagnostic and therapeutic.


Asunto(s)
Enfermedad de Castleman/patología , Enfermedad de Castleman/cirugía , Anciano , Enfermedad de Castleman/diagnóstico por imagen , Diagnóstico Diferencial , Duodeno/patología , Humanos , Masculino , Páncreas/patología , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
7.
G Chir ; 28(10): 367-70, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17915050

RESUMEN

Desmoplastic small round cell tumor (DSRCT) is a rare, highly aggressive malignancy with distinctive histological and immunohistochemical features occurring in young population with male predominance. We report a case of DRSCT occurred in a 17 years old patient which presented with a large upper left quadrant abdominal mass that was treated with a very aggressive surgical approach and multi-agent chemotherapy. At a 12 months follow-up he is free of recurrence. This kind of tumour has a very poor prognosis. No standard treatment protocol has been established. Aggressive surgery combined with postoperative multi-agent adjuvant chemotherapy is justified not only to relieve symptoms but also to try to improve the outcome.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Fibromatosis Agresiva/tratamiento farmacológico , Fibromatosis Agresiva/cirugía , Neoplasias Retroperitoneales/tratamiento farmacológico , Neoplasias Retroperitoneales/cirugía , Adolescente , Carcinoma de Células Pequeñas/tratamiento farmacológico , Carcinoma de Células Pequeñas/cirugía , Quimioterapia Adyuvante , Dactinomicina/administración & dosificación , Doxorrubicina/administración & dosificación , Fibromatosis Agresiva/diagnóstico por imagen , Humanos , Ifosfamida/administración & dosificación , Masculino , Neoplasias Retroperitoneales/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Vincristina/administración & dosificación
8.
Int J Pharm ; 528(1-2): 299-311, 2017 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-28596143

RESUMEN

Quality control analysis of nanomaterials has been identified as a major issue to pursue their development in different industrial fields including nanomedicine. One difficulty is the lack of standardized and validated protocols suitable to achieve their characterization. In a previous work, we have developed standardized protocols for the evaluation of the size and zeta potential of nanomaterials based on methods described in the ISO standard and have performed validation of each one. The present work was aimed to transfer these protocols in three independent receiving laboratories. No official guideline was described in the literature to achieve such a transfer. A comparative study for receiving laboratories equipped with the same instrument as the sending laboratory was designed based on the Code of Federal Regulation edited by the Food and Drug Administration. For the receiving laboratory equipped with an instrument working at a different wavelength, a new validation was designed and applied. Corresponding statistical methods were used for the analysis of the results. A successful transfer of the protocols in all receiving laboratories was achieved. All laboratories recorded consistent results applying in blind the protocol of size measurements on two samples of nanomaterials from which included one reference.


Asunto(s)
Dispersión Dinámica de Luz , Nanoestructuras/análisis , Control de Calidad , Laboratorios , Nanomedicina , Tamaño de la Partícula
9.
Eur J Pain ; 20(8): 1326-34, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-26914965

RESUMEN

BACKGROUND: Injection of the noxious peptide Bv8 has previously been shown to induce a biphasic thermal hyperalgesia in rodents, the first peak presumably due to peripheral sensitization. This hypothesis has never been directly confirmed. We have assessed whether Bv8 can indeed sensitize peripheral nerve fibres in the mouse to heat. METHODS: We used recordings from single cutaneous fibres, cutaneous calcitonin gene-related peptide (CGRP) release and immunostaining in nerves and plantar skin to evaluate the Bv8 effects on cutaneous nerves. RESULTS: Application of Bv8 at nanomolar concentrations (30-310 nmol/L) to skin preparations significantly increased the heat-induced discharge, the heat-induced afterdischarge and reduced threshold temperature of single unmyelinated polymodal fibres. Furthermore, application of Bv8 to hind-paw skin flaps or trigeminal ganglia significantly elevated their heat-induced CGRP release. Capsaicin-induced and to a lesser extent also KCl-induced CGRP releases were also augmented after Bv8 treatment. Immunohistochemistry revealed co-localization of prokineticin 2 (Bv8 ortholog in rodents) and CGRP in both plantar skin and nerve tissues. These results confirm that Bv8 sensitizes cutaneous nerve endings to heat, partly, although not exclusively through TRPV1 activation. CONCLUSION: Our results thus support the hypothesis that the first hyperalgesic phase to follow Bv8 injection to hind paws of intact animals is due to peripheral sensitization of nociceptors. WHAT DOES THIS STUDY ADD?: Our data provide mechanistic insights into the effect Bv8 application exerts on afferent nerve endings and into the concomitant development of thermal hyperalgesia.


Asunto(s)
Hormonas Gastrointestinales , Hiperalgesia/etiología , Fibras Nerviosas/efectos de los fármacos , Neuropéptidos , Nervios Periféricos/efectos de los fármacos , Piel/inervación , Animales , Péptido Relacionado con Gen de Calcitonina/metabolismo , Capsaicina/farmacología , Modelos Animales de Enfermedad , Femenino , Calor , Masculino , Ratones , Ratones Endogámicos C57BL , Nociceptores/fisiología
10.
Chir Organi Mov ; 90(3): 271-9, 2005.
Artículo en Inglés, Italiano | MEDLINE | ID: mdl-16681104

RESUMEN

A retrospective study was conducted to evaluate the results of two-stage surgical treatment for infected hip implant using two different spacers in antibiotic-impregnated cement, one custom-made and one pre-formed. Out of a total of 20 patients treated between 1995 and 2003, the temporary implant of one custom-made spacer was carried out in 8 cases, while in the remaining 12 cases we resorted to using a pre-formed spacer (Spacer G). In both groups we observed one recurrence of infection, for an overall 90% success rate in terms of eradication of the infection. Custom-made spacers had a greater incidence of local complications (1 breakage, 1 dislocation, 1 sinking of the revision stem) as compared to pre-formed ones (1 dislocation). The clinical results evaluated using the Harris Hip Score showed a statistically significant difference (p < 0.05) in both groups as compared to the preoperative score. The use of a pre-formed spacer, although more costly as compared to that custom-made one, was advantageous in some ways, for example in terms of standardization of the implant method, the lower incidence of mechanical complications and the better functional results.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Infecciones Relacionadas con Prótesis/cirugía , Anciano , Artroplastia de Reemplazo de Cadera/instrumentación , Artroplastia de Reemplazo de Cadera/métodos , Femenino , Estudios de Seguimiento , Prótesis de Cadera/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Diseño de Prótesis , Reoperación , Factores de Tiempo
11.
Endocrinology ; 111(2): 693-5, 1982 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7094889

RESUMEN

The effect of sauvagine (SAU), a frog skin peptide, on prolactin (PRL) levels was studied in vivo and in vitro. Subcutaneous administration of SAU (20 micrograms/kg) reduced plasma PRL levels in normal adult male rats and suppressed the suckling-induced rise of PRL in lactating rats even at doses of 1 and 5 micrograms/kg. Perfusion of isolated and dispersed rat pituitary cells in vitro with increasing doses of SAU (from 5 x 10(-10) to 1.7 x 10(-8)M) induced a significant dose-related decrease of PRL secretion in the eluate. These results indicate that SAU is a potent PRL inhibiting factor and that its action is exerted at the pituitary level. If SAU or a SAU-related peptide is present in the mammalian brain, it can be tentatively hypothesized that this peptide plays an important role in the control of PRL secretion.


Asunto(s)
Péptidos/farmacología , Prolactina/antagonistas & inhibidores , Proteínas Anfibias , Animales , Bromocriptina/farmacología , Dopamina/farmacología , Relación Dosis-Respuesta a Droga , Masculino , Hormonas Peptídicas , Perfusión , Adenohipófisis/efectos de los fármacos , Adenohipófisis/metabolismo , Ratas , Ratas Endogámicas , Factores de Tiempo
12.
FEBS Lett ; 429(1): 41-3, 1998 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-9657380

RESUMEN

We have isolated a cDNA encoding a precursor of dermorphin from the skin of Pachymedusa dacnicolor. Besides four copies of this opioid peptide, the deduced sequence also contains the genetic information for a novel peptide Tyr-Ile-Phe-His-Leu-Met-Asp-NH2. This differs from Met-deltorphin by the presence of Ile at position 2. In a related precursor from the skin of Agalychnis annae, the sequence of this peptide is in the 3'-untranslated region of the cloned cDNA. From earlier results we predict that in skin peptides the second residue is D-allo-Ile. We have synthesized this and related peptides with different D-amino acids, and determined their delta agonist activity. The peptide with D-nor-Leu binds with high affinity to delta receptors, while that with D-allo-Ile is about 100 times less active.


Asunto(s)
Anuros/genética , ADN Complementario/análisis , Oligopéptidos/genética , Péptidos Opioides/genética , Secuencia de Aminoácidos , Animales , Datos de Secuencia Molecular , Oligopéptidos/efectos de los fármacos , Péptidos Opioides/química , Péptidos Opioides/farmacología , Alineación de Secuencia , Homología de Secuencia de Aminoácido
13.
FEBS Lett ; 302(2): 151-4, 1992 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-1633846

RESUMEN

Skin extracts of South American hylid frogs of the subfamily Phyllomedusinae contain dermorphins and deltorphins, opioid heptapeptides highly selective for either mu or delta receptors. In all these peptides, a D-amino acid is present in the second position. The structure of the precursors for Ala-deltorphins was recently deduced from cloned cDNAs derived from skin of Phyllomedusa bicolor (Richter et al. (1990) Proc. Natl. Acad. Sci. USA 87, 4836-4839). From the amino acid sequence of these precursors, the existence of three peptides related to dermorphin could be predicted. From methanol extracts of skin of Ph. bicolor we have isolated two of these peptides, [Lys7]dermorphin-OH and [Trp4,Asn7]dermorphin-OH. The biological activity of these new dermorphins and their amidated counterparts is presented.


Asunto(s)
Anuros , Oligopéptidos/aislamiento & purificación , Piel/química , Secuencia de Aminoácidos , Animales , Cromatografía Líquida de Alta Presión , Cobayas , Intestino Delgado/fisiología , Masculino , Ratones , Datos de Secuencia Molecular , Contracción Muscular/efectos de los fármacos , Oligopéptidos/química , Oligopéptidos/farmacología , Péptidos Opioides , Conducto Deferente/fisiología
14.
J Med Chem ; 42(3): 400-4, 1999 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-9986710

RESUMEN

In the present paper we describe the synthesis of some dermorphin and deltorphin analogues beta-O- and alpha-C-glycosylated on the C-terminal amino acid residue and report their opioid receptor affinity and selectivity as well as their analgesic potency after subcutaneous injection in mice.


Asunto(s)
Analgésicos Opioides/síntesis química , Oligopéptidos/síntesis química , Secuencia de Aminoácidos , Analgésicos Opioides/química , Analgésicos Opioides/farmacología , Animales , Glicosilación , Cobayas , Técnicas In Vitro , Inyecciones Subcutáneas , Masculino , Ratones , Músculo Liso/efectos de los fármacos , Oligopéptidos/química , Oligopéptidos/farmacología , Péptidos Opioides , Receptores Opioides/efectos de los fármacos
15.
Neuroscience ; 106(3): 469-80, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11591451

RESUMEN

The opioid receptor-like 1 (ORL1) receptor shares a high degree of sequence homology with the classical mu-, delta- and kappa-opioid receptors and a functional mutual opposition between these receptors has been suggested. To further address this possible interaction we have used mu-, delta- and kappa-opioid receptor knockout mice to determine autoradiographically if there are any changes in the number or distribution of the ORL1 receptor, labelled with [(3)H]nociceptin, in the brains of mice deficient in each of the opioid receptors. An up-regulation of ORL1 expression was observed across all brain regions in delta-knockouts with cortical regions typically showing a 15-30% increase in binding that was most marked in heterozygous mice. In contrast, ORL1 receptor expression was down-regulated in virtually all brain structures in heterozygous kappa-knockouts although the magnitude of this change was not as great as for the delta-knockouts. No significant alterations in ORL1 receptor expression were observed across brain regions in mu-receptor knockout mice and there were no qualitative differences in ORL1 receptor expression in any groups. These data suggest there are interactions between the ORL1 system and the classical opioid receptors and that the interactions are receptor-specific. The greater differences observed in heterozygous mice suggest that these interactions might be most relevant when there is only partial loss of receptor function.


Asunto(s)
Encéfalo/metabolismo , Dolor/metabolismo , Receptores Opioides delta/deficiencia , Receptores Opioides kappa/deficiencia , Receptores Opioides mu/deficiencia , Receptores Opioides/metabolismo , Animales , Encéfalo/citología , Encéfalo/efectos de los fármacos , Mapeo Encefálico , Regulación hacia Abajo/genética , Femenino , Masculino , Ratones , Ratones Noqueados , Péptidos Opioides/antagonistas & inhibidores , Péptidos Opioides/metabolismo , Péptidos Opioides/farmacocinética , Dolor/fisiopatología , Ensayo de Unión Radioligante , Receptores Opioides/efectos de los fármacos , Receptores Opioides delta/genética , Receptores Opioides kappa/genética , Receptores Opioides mu/genética , Valores de Referencia , Tritio/farmacocinética , Regulación hacia Arriba/genética , Receptor de Nociceptina , Nociceptina
16.
Br J Pharmacol ; 114(1): 57-66, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7712029

RESUMEN

1. The opioid activity of the amphibian peptide, [Lys7]dermorphin, was studied in rats and mice. When administered intracerebroventricularly (i.c.v.), intravenously (i.v.) or subcutaneously (s.c.) it produced a long lasting analgesia. Its antinociceptive potency exceeded that of morphine 290 times by i.c.v. injection, and 25-30 times by peripheral administration. 2. The dose-response curves of [Lys7]dermorphin antinociception were shifted to the right by the pretreatment with naloxone (0.1 mg kg-1, s.c.) or with the mu 1-selective antagonist, naloxonazine (10 mg kg-1, i.v. 24 h before peptide injection). 3. The peptide also displayed potent antinociceptive effects in a chronic inflammatory pain model (rat Freund's adjuvant arthritis). In this pain model, systemic administration of the peptide raised the nociceptive threshold more in inflamed than in healthy paw. 4. High central and peripheral doses of [Lys7]dermorphin in rats produced catalepsy. The cataleptic response was antagonized by naloxone but left unchanged by naloxonazine pretreatment. 5. In rats and mice, central or peripheral administration of [Lys7]dermorphin induced a significantly slower development of tolerance to the antinociceptive effect than did morphine. 6. Upon naloxone precipitation of the withdrawal syndrome, [Lys7]dermorphin-dependent mice made fewer jumps and lost less weight than the morphine-dependent animals. Withdrawal hyperalgesia did not develop in [Lys7]dermorphin-dependent mice. 7. In conclusion, [Lys7]dermorphin seems to be a unique opioid peptide having a high penetration into the blood-brain barrier despite its low lipid solubility. This peptide causes fewer side-effects than other opioids and appears less likely than morphine to cause physical dependence in rats and mice.


Asunto(s)
Nociceptores/efectos de los fármacos , Oligopéptidos/farmacología , Receptores Opioides mu/efectos de los fármacos , Analgésicos Opioides/farmacología , Animales , Peso Corporal/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Tolerancia a Medicamentos , Masculino , Ratones , Morfina/farmacología , Naloxona/farmacología , Nociceptores/fisiología , Péptidos Opioides , Ratas , Ratas Wistar , Receptores Opioides mu/fisiología , Trastornos Relacionados con Sustancias/metabolismo
17.
Br J Pharmacol ; 124(2): 345-55, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9641552

RESUMEN

1. Changes in respiratory variables, arterial blood pressure and heart rate were studied in awake rats after injection of the opioid peptide [Lys7]dermorphin and its main metabolites, [1-5]dermorphin and [1-4]dermorphin. 2. Fifteen minutes after injection, doses of [Lys7]dermorphin producing antinociception (i.c.v., 36-120 nmol; s.c., 0.12-4.7 micromol kg(-1)) significantly increased respiratory frequency and minute volume of rats breathing air or hypoxic inspirates. This respiratory stimulation was reversed to depression by the 5-HT receptor antagonist ritanserin (2 mg kg(-1), s.c.), was blocked by naloxone (0.1 mg kg(-1), s.c.), significantly reduced by the mu1 opioid receptor antagonist naloxonazine (10 mg kg(-1), s.c., 24 h before) but unaffected by peripherally acting opioid antagonist naloxone methyl bromide (3 mg kg(-1), s.c.). Forty five minutes after injection, doses of the peptide producing catalepsy (s.c., 8.3-14.2 micromol kg(-1), i.c.v., 360 nmol) significantly reduced respiratory frequency and volume of rats breathing air and blocked the hypercapnic ventilator response of rats breathing from 4% to 10% CO2. I.c.v. administration of [1-5]dermorphin and [1-4]dermorphin (from 36 to 360 nmol) never stimulated respiration but significantly reduced basal and CO2-stimulated ventilation. Opioid respiratory depression was only antagonized by naloxone. 3. In awake rats, [Lys7]dermorphin (0.1-1 mg kg(-1), s.c.) decreased blood pressure. This hypotensive response was abolished by naloxone, reduced by naloxone methyl bromide and unaffected by naloxonazine. 4. In conclusion, the present study indicates that analgesic doses of [Lys7]dermorphin stimulate respiration by activating central mu1 opioid receptors and this respiratory stimulation involves a forebrain 5-hydroxytryptaminergic excitatory pathway.


Asunto(s)
Analgesia , Oligopéptidos/farmacología , Ventilación Pulmonar/efectos de los fármacos , Receptores Opioides mu/agonistas , Antagonistas de la Serotonina/farmacología , Animales , Presión Sanguínea/efectos de los fármacos , Hipercapnia/inducido químicamente , Inyecciones Intravenosas , Inyecciones Intraventriculares , Inyecciones Subcutáneas , Masculino , Naloxona/administración & dosificación , Naloxona/análogos & derivados , Naloxona/metabolismo , Naloxona/farmacología , Antagonistas de Narcóticos/farmacología , Oligopéptidos/administración & dosificación , Prosencéfalo/efectos de los fármacos , Prosencéfalo/metabolismo , Compuestos de Amonio Cuaternario , Ratas , Ratas Wistar , Ritanserina/administración & dosificación , Ritanserina/farmacología , Antagonistas de la Serotonina/administración & dosificación , Volumen de Ventilación Pulmonar/efectos de los fármacos
18.
Br J Pharmacol ; 128(7): 1554-60, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10602336

RESUMEN

1. To reduce the density of delta-opioid receptor protein, five antisense phosphorothioate oligodeoxynucleotides (aODN), targeting the three exons of rat delta-opioid receptor mRNA (DOR), were injected twice daily for 4 days or continuously infused for 7 days into brain lateral ventricles (i.c.v.) of Sprague-Dawley rats. Rats acting as controls were infused or injected with a mismatch sequence (mODN) of each aODN. The density of opioid receptors in rat brain membranes was measured by saturation binding experiments using selective ligands for delta, mu and kappa opioid receptors. 2. aODNs injected twice a day for 4 days left rat brain delta-opioid receptor density unchanged. The ODN targeting the DOR nucleotide sequence 280 - 299 (aODN280 - 299, exon 2), decreased brain delta-opioid receptor density significantly more than aODNs targeting exon 1 (aODN239 - 258), exon 2 (aODN361 - 380), or exon 3 (aODN741 - 760) (to 52% vs 79, 72, and 68%). None of the aODNs to the DOR changed the brain density of mu- or k-opioid receptors. 3. When in a novel environment (but not when kept in their home cages), the locomotor activity of aODN280 - 299 treated rats was significantly lower than that of saline or mODN treated rats. The delta-opioid agonist SNC80 (5 mg kg-1, s.c.) significantly and potently stimulated locomotion and delayed colonic propulsion in saline- and mODN-infused rats, but left motor behaviour and colonic transit of delta-knockdown rats unchanged. 4. The baseline nociceptive threshold and the antinociceptive response to morphine were unchanged in delta-knockdown rats.


Asunto(s)
Benzamidas/farmacología , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Colon/efectos de los fármacos , Tránsito Gastrointestinal/efectos de los fármacos , Actividad Motora/efectos de los fármacos , Oligodesoxirribonucleótidos Antisentido/farmacología , Piperazinas/farmacología , Receptores Opioides delta/biosíntesis , Tionucleótidos/farmacología , Analgésicos Opioides/farmacología , Animales , Conducta Animal/efectos de los fármacos , Colon/fisiología , Tránsito Gastrointestinal/fisiología , Inyecciones Intraventriculares , Masculino , Morfina/farmacología , Actividad Motora/fisiología , Nociceptores/efectos de los fármacos , Nociceptores/fisiología , Oligodesoxirribonucleótidos Antisentido/genética , ARN Mensajero/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores Opioides delta/genética , Receptores Opioides delta/metabolismo , Tionucleótidos/genética
19.
Br J Pharmacol ; 45(2): 333-48, 1972 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-5048651

RESUMEN

1. Methanol extracts of the skin of Bombina bombina and Bombina variegata variegata, two European discoglossid frogs, contain an active tetradecapeptide, bombesin. Alytesin, a tetradecapeptide strictly related to bombesin is present in extracts of the skin of Alytes obstetricans, another European discoglossid frog. The American frog Rana pipiens, contains in its skin ranatensin, an endecapeptide related to bombesin and alytesin.2. Passage of crude skin extracts of Bombina through a column of alumina yields eluates which may be considered free of other peptide contaminants and are suitable for the isolation of bombesin in a pure form.3. Bombesin has a stimulant action on several preparations of intestinal, uterine and urinary tract smooth muscle. Sometimes the effect is easily repeatable and shows a fair proportionality to the dose, but at other times a prompt and intense tachyphylaxis is observed. Other smooth muscle preparations are poorly sensitive or insensitive to bombesin. The rat uterus, the kitten small intestine, the guinea-pig colon and the rat urinary bladder may be used for the quantitative bioassay of bombesin.4. Bombesin-like peptides may easily be distinguished from all other naturally occurring peptides by parallel assay. They constitute a new group of active peptides possessing a peculiar spectrum of activity.


Asunto(s)
Anuros , Músculo Liso/efectos de los fármacos , Péptidos/farmacología , Piel/análisis , Secuencia de Aminoácidos , Animales , Pollos , Cromatografía , Cricetinae , Cobayas , Técnicas In Vitro , Inyecciones Intravenosas , Péptidos/análisis , Péptidos/aislamiento & purificación , Conejos , Ratas , Extractos de Tejidos , Tortugas
20.
Br J Pharmacol ; 124(7): 1516-22, 1998 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9723966

RESUMEN

1. In order to improve the in vivo stability of the opioid peptide dermorphin we synthesized O-betaglucosylated analogs ([Ser7-O-betaGlc]dermorphin and [Ser7-O-betaGlc(Ac)4]-dermorphin) and C-alphagalactosylated analogs ([Ala7-C-alphaGal]dermorphin and [Ala7-C-alphaGal(Ac)4]-dermorphin). 2. O- and C-glycosylation of dermorphin halved the peptide affinity for brain mu-opioid receptors and the biological potency in guinea-pig ileum assay (GPI). Despite their lower opioid receptor affinity, when administered intracerebroventricularly (i.c.v., 8-40 pmol) and subcutaneously (s.c., 0.5-3 micromol kg(-1)) in rats, glycosylated analogs were two times more potent than dermorphin in reducing the nociceptive response to radiant heat. Acetylation of sugar hydroxyl groups reduces 5-10 times both biological activity on GPI and mu-receptor affinity, whereas the antinociceptive potency was equal to (i.c.v.) or only two-three times lower (s.c.) than dermorphin potency. 3. Blood-Brain Barrier Permeability Index (BBB-PI) of the glycodermorphins was significantly higher than that of dermorphin, indicating a facilitated entry into the brain: O-beta-linked glucoconiugates are expected to enter CNS by the glucose transporter GLUT-1 of the endothelial barrier. However the calculated BBB-PI for the C-alphagalactoside was about two times higher than that of the O-betaglucoside, excluding the implication of GLUT-1 that is known to be selective for O-beta-links and preferring for the exose glucose. 4. The enhanced brain permeability with the subsequent decrease in peripheral dosage of these opioid peptides did not result in lowering constipation.


Asunto(s)
Analgésicos Opioides/farmacología , Barrera Hematoencefálica , Péptidos Opioides/farmacología , Secuencia de Aminoácidos , Analgésicos Opioides/farmacocinética , Animales , Colon/efectos de los fármacos , Colon/fisiología , Motilidad Gastrointestinal/efectos de los fármacos , Cobayas , Semivida , Íleon/efectos de los fármacos , Íleon/fisiología , Técnicas In Vitro , Masculino , Ratones , Naloxona/farmacología , Péptidos Opioides/farmacocinética , Receptores Opioides/efectos de los fármacos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA