RESUMEN
INTRODUCTION: Neuropathological findings in Dravet Syndrome (DS) are scarce, especially in adult patients, and often do not have a genetic confirmation. Additionally, the missense SCN1A pathogenic variant found has only been described as de novo mutation in previous literature. METHODS: We describe the clinical and genetic findings of a family (including three sisters and his father), using Sanger sequencing in the three sisters and in postmortem brain tissue in the father. The present study also shows the neuropathological findings of the father. RESULTS: Despite the presence of long term drug resistant epilepsy, starting with febrile seizures between 6 and 12 months of age, and intellectual disability (ID), the three sisters were diagnosed with DS in adulthood, identifying a missense SCN1A pathogenic variant in exon 20, previously described as de novo -p.Gly1332Glu (c .3995 G>A). The oldest sister had the most severe phenotype, with severe ID and wheel chair dependency, passing away at 52. The other two sisters had a moderate phenotype, being at the present seizure free, but with significant comorbidities, such as crouch gait and parkinsonism. Several relatives from the paternal path (including the father) presented epilepsy, but without ID. The father was diagnosed with Alzheimer´s Disease (AD) at 60, and because he donated his brain, the same variant was confirmed in postmortem study. Neither the MRI nor the histopathology showed specific morphological changes for DS, consistent with previous studies. CONCLUSIONS: This work supports the need to review the clinical and genetic spectra of DS in adults with epilepsy and unknown ID. The clinical consequences of this syndrome seem to have a functional rather than a structural basis, supported by the absence of specific neuropathological findings.
Asunto(s)
Epilepsias Mioclónicas , Epilepsia , Adulto , Humanos , Masculino , Epilepsias Mioclónicas/genética , Mutación , Mutación Missense , Canal de Sodio Activado por Voltaje NAV1.1/genética , Fenotipo , LactanteRESUMEN
INTRODUCTION: Traumatic brain injury (TBI) is a common cause of death and disability in the paediatric population, although the literature on the Spanish population is scarce. From the perspective of early vulnerability, recent research findings suggest that early brain injury has worse sequelae and a higher risk of impact. AIMS: To analyse the intelligence profile, executive functions and behaviour, and examine the association between age at the time of the injury, severity of the TBI and environmental factors for cognitive and behavioural outcomes. PATIENTS AND METHODS: Seventy-one participants with moderate to severe TBI, from 6 to 16 years of age, were assessed with measures of intelligence (intelligence quotient), executive functions and behaviour. RESULTS: Children with TBI are at increased risk of disability in all aspects of intelligence, executive functions and behaviour. Children who suffered a traumatic brain injury in infancy and the preschool period had more overall effects on intelligence quotient and some aspects of the executive functions. CONCLUSIONS: Socioeconomic and cultural factors are the best predictors for intelligence quotient and behaviour. These findings contribute to a better understanding of the sequelae of TBI in children, which will help in rehabilitation planning and re-adaptation to functional life.
TITLE: Perfil y factores pronósticos en el traumatismo craneoencefálico en la edad pediátrica.Introducción. El traumatismo craneoencefálico (TCE) es una causa común de muerte y discapacidad en la población pediátrica, aunque la bibliografía en población española sea escasa. Desde la perspectiva de la vulnerabilidad temprana, los hallazgos de investigaciones recientes sugieren que la lesión cerebral temprana tiene peores secuelas y un mayor riesgo de impacto. Objetivos. Analizar el perfil de la inteligencia, las funciones ejecutivas y el comportamiento, y examinar la asociación de la edad a la lesión, la gravedad del TCE y los factores ambientales para los resultados cognitivos y conductuales. Pacientes y métodos. Setenta y un participantes con TCE moderado a grave, con edades entre 6 y 16 años, fueron evaluados con medidas de inteligencia (cociente intelectual), funciones ejecutivas y comportamiento. Resultados. Los niños con TCE tienen un mayor riesgo de discapacidad en todos los aspectos de inteligencia, funciones ejecutivas y comportamiento. Los niños que sufrieron una lesión cerebral traumática en la infancia y preescolar registraron más efectos globales en el cociente intelectual y algunos aspectos de las funciones ejecutivas. Conclusiones. Los factores socioeconómicos y culturales son los mejores predictores para el cociente intelectual y el comportamiento. Estos hallazgos contribuyen a una mejor comprensión de las secuelas de TCE en los niños para ayudar en la planificación de rehabilitación y la readaptación a la vida funcional.
Asunto(s)
Conducta , Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/psicología , Función Ejecutiva , Inteligencia , Adolescente , Niño , Estudios Transversales , Femenino , Humanos , Puntaje de Gravedad del Traumatismo , Masculino , Pronóstico , Factores de TiempoRESUMEN
INTRODUCTION: Traumatic brain injury is a common cause of acquired disability during childhood. Early interventions focusing on parenting practices may prove effective at reducing negative child outcomes. AIM: To determine the efficacy of a new counselling program aimed at parents and schools compared to a control group. PATIENTS AND METHODS: The main study sample was obtained from a paediatric hospital. The final sample consisted of 42 children aged between 6 and 16 years old. RESULTS: Comparing with normative data, pre-post comparisons between groups showed a significant improvement in the parent group with respect to the control group. CONCLUSIONS: The superiority of the parental intervention group over those of the control group was not only statistically significant, but also clinically substantial and meaningful. The results of this study suggest that children with moderate to severe traumatic brain injury can benefit from an intensive supported family treatment.
TITLE: Eficacia de una nueva intervencion de apoyo a padres y escuelas despues de un traumatismo craneoencefalico moderado o grave.Introduccion. El traumatismo craneoencefalico es una causa habitual de discapacidad adquirida durante la infancia. Las intervenciones tempranas que se centran en la participacion de los padres pueden resultar efectivas para reducir las disfunciones del niño. Objetivo. Determinar la eficacia de un nuevo programa de asesoramiento dirigido a padres y escuelas en comparacion con un grupo control. Pacientes y metodos. La muestra principal del estudio se obtuvo de un hospital pediatrico. La muestra final consistio en 42 niños de 6 a 16 años. Resultados. Comparando con los datos normativos, las comparaciones pre y post intragrupos mostraron una mejora significativa en el grupo de intervencion parental con respecto al grupo control. Conclusiones. La superioridad del grupo de intervencion parental sobre el grupo control no solo fue estadisticamente significativa, sino tambien clinicamente sustancial y relevante. Los resultados del estudio sugieren que los niños con traumatismo craneoencefalico moderado o grave pueden beneficiarse de un tratamiento familiar intensivo de apoyo.
Asunto(s)
Lesiones Traumáticas del Encéfalo/rehabilitación , Consejo , Padres/educación , Educación del Paciente como Asunto , Instituciones Académicas , Formación del Profesorado/organización & administración , Adolescente , Terapia Conductista , Daño Encefálico Crónico/etiología , Daño Encefálico Crónico/rehabilitación , Lesiones Traumáticas del Encéfalo/epidemiología , Niño , Trastornos de la Conducta Infantil/etiología , Trastornos de la Conducta Infantil/rehabilitación , Trastornos del Conocimiento/etiología , Trastornos del Conocimiento/rehabilitación , Educación Especial , Femenino , Humanos , Masculino , Relaciones Padres-Hijo , Responsabilidad Parental , Educación del Paciente como Asunto/organización & administración , Evaluación de Programas y Proyectos de Salud , España/epidemiologíaRESUMEN
Deep sedation during stay in the Intensive Care Unit (ICU) may have deleterious effects upon the clinical and cognitive outcomes of critically ill patients undergoing mechanical ventilation. Over the last decade a vast body of literature has been generated regarding different sedation strategies, with the aim of reducing the levels of sedation in critically ill patients. There has also been a growing interest in acute brain dysfunction, or delirium, in the ICU. However, the effect of sedation during ICU stay upon long-term cognitive deficits in ICU survivors remains unclear. Strategies for reducing sedation levels in the ICU do not seem to be associated with worse cognitive and psychological status among ICU survivors. Sedation strategy and management efforts therefore should seek to secure the best possible state in the mechanically ventilated patient and lower the prevalence of delirium, in order to prevent long-term cognitive alterations (AU)
La sedación profunda durante la estancia en una Unidad de Cuidados Intensivos (UCI) puede afectar negativamente al estado clínico y cognitivo de los pacientes críticos sometidos a ventilación mecánica. En la última década ha aparecido gran cantidad de literatura sobre diferentes estrategias dirigidas a reducir los niveles de sedación en el paciente crítico. Además, ha aumentado el interés sobre la disfunción cerebral aguda o delirium. Sin embargo, el efecto de la sedación sobre los déficits cognitivos a largo plazo continúa siendo poco conocido. Las estrategias centradas en reducir los niveles de sedación en UCI no parecen estar asociadas con un peor estado cognitivo y psicológico de los supervivientes. Por lo tanto, las estrategias de manejo de la sedación en UCI deberían focalizarse en mejorar el estado del paciente ventilado, así como en disminuir el delirium, con el fin de prevenir las alteraciones cognitivas a largo plazo (AU)
Asunto(s)
Humanos , Masculino , Femenino , Analgesia/métodos , Disonancia Cognitiva , Cuidados Críticos/organización & administración , Cuidados Críticos/normas , Sedación Profunda/métodos , Sedación Profunda/tendencias , Sedación Profunda , Trastornos Neurocognitivos/tratamiento farmacológico , Trastornos Neurocognitivos/prevención & control , Sobrevivientes/psicología , Sobrevivientes/estadística & datos numéricosRESUMEN
Deep sedation during stay in the Intensive Care Unit (ICU) may have deleterious effects upon the clinical and cognitive outcomes of critically ill patients undergoing mechanical ventilation. Over the last decade a vast body of literature has been generated regarding different sedation strategies, with the aim of reducing the levels of sedation in critically ill patients. There has also been a growing interest in acute brain dysfunction, or delirium, in the ICU. However, the effect of sedation during ICU stay upon long-term cognitive deficits in ICU survivors remains unclear. Strategies for reducing sedation levels in the ICU do not seem to be associated with worse cognitive and psychological status among ICU survivors. Sedation strategy and management efforts therefore should seek to secure the best possible state in the mechanically ventilated patient and lower the prevalence of delirium, in order to prevent long-term cognitive alterations.
Asunto(s)
Analgesia/efectos adversos , Trastornos del Conocimiento/inducido químicamente , Cuidados Críticos , Sedación Profunda/efectos adversos , Sobrevivientes , Analgésicos/efectos adversos , Trastornos del Conocimiento/fisiopatología , Trastornos del Conocimiento/prevención & control , Estudios de Cohortes , Enfermedad Crítica/psicología , Sedación Profunda/métodos , Delirio/inducido químicamente , Delirio/fisiopatología , Delirio/prevención & control , Humanos , Hipnóticos y Sedantes/efectos adversos , Unidades de Cuidados Intensivos , Ensayos Clínicos Controlados Aleatorios como Asunto , Respiración Artificial/efectos adversos , Factores de Riesgo , Sobrevivientes/psicología , Lesión Pulmonar Inducida por Ventilación Mecánica/fisiopatología , Lesión Pulmonar Inducida por Ventilación Mecánica/psicologíaRESUMEN
Patients with acute lung injury or acute respiratory distress syndrome (ARDS) admitted to the ICU present neuropsychological alterations, which in most cases extend beyond the acute phase and have an important adverse effect upon quality of life. The aim of this review is to deepen in the analysis of the complex interaction between lung and brain in critically ill patients subjected to mechanical ventilation. This update first describes the neuropsychological alterations occurring both during the acute phase of ICU stay and at discharge, followed by an analysis of lung-brain interactions during mechanical ventilation, and finally explores the etiology and mechanisms leading to the neurological disorders observed in these patients. The management of critical patients requires an integral approach focused on minimizing the deleterious effects over the short, middle or long term.
Asunto(s)
Encéfalo/fisiopatología , Trastornos del Conocimiento/etiología , Confusión/etiología , Delirio/etiología , Pulmón/fisiopatología , Respiración Artificial , Enfermedad Aguda , Lesión Pulmonar Aguda/psicología , Lesión Pulmonar Aguda/terapia , Atención , Barrera Hematoencefálica , Daño Encefálico Crónico/etiología , Daño Encefálico Crónico/fisiopatología , Daño Encefálico Crónico/psicología , Catecolaminas/fisiología , Trastornos del Conocimiento/fisiopatología , Confusión/fisiopatología , Enfermedad Crítica/psicología , Citocinas/fisiología , Delirio/fisiopatología , Función Ejecutiva , Humanos , Hipoxia Encefálica/etiología , Hipoxia Encefálica/psicología , Hipoxia Encefálica/terapia , Unidades de Cuidados Intensivos , Neuropéptidos/fisiología , Pruebas Neuropsicológicas , Respiración Artificial/efectos adversos , Síndrome de Dificultad Respiratoria/psicología , Síndrome de Dificultad Respiratoria/terapiaRESUMEN
The interaction of central opioid with adrenergic system in stimulation of the hypothalamic-pituitary-adrenal (HPA) axis was investigated in conscious rats. All the tested drugs were administered intracerebroventricularly (i.c.v.), naloxone 15 min before the adrenergic agonists. Phenylephrine (30 micrograms), clonidine (10 micrograms) and isoprenaline (10 micrograms), the alpha 1-, alpha 2- and beta-adrenergic agonists as well as noradrenaline (10 micrograms) and adrenaline (10 micrograms) significantly increased the serum corticosterone levels, measured 1 h after drug administration. Naloxone (0.01-1 microgram) did not markedly influence the corticosterone response to phenylephrine and isoprenaline and diminished by a half the response to clonidine. Naloxone also significantly decreased the corticosterone response to noradrenaline but did not substantially alter the response to adrenaline. Noradrenaline potently stimulates the HPA axis via alpha 2-adrenoceptors, whereas adrenaline involves mainly alpha 1- and beta-adrenergic receptors. These results indicate that central opioid system is significantly involved in mediating the pituitary-adrenocortical response to clonidine and noradrenaline but not phenylephrine, isoprenaline and adrenaline. This suggests an interaction of opioids at central alpha 2- but not alpha 1-receptor sites.
Asunto(s)
Corticosterona/sangre , Naloxona/farmacología , Antagonistas de Narcóticos/farmacología , Corteza Suprarrenal/efectos de los fármacos , Animales , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Epinefrina/farmacología , Inyecciones Intraventriculares , Isoproterenol/farmacología , Masculino , Norepinefrina/farmacología , Fenilefrina/farmacología , Hipófisis/efectos de los fármacos , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Prazosina/farmacología , Ratas , Ratas WistarRESUMEN
A 1.3-kb segment of Escherichia coli DNA containing the regulatory gene, araC, and the promoter of the araBAD operon was amplified by the polymerase chain reaction (PCR) and cloned into pUC18, resulting in plasmid pKB130 that produced the alpha fragment of beta-galactosidase upon addition of L-arabinose (L-ara). A synthetic gene for human immunodeficiency virus (HIV)-1 preprotease was placed downstream of the ara-BAD promoter in pKB130 to create a translational fusion inducible by addition of L-ara. The fusion protein correctly autoprocessed in vivo to yield a mature 99-amino-acid HIV-1 protease, which was found predominantly in inclusion bodies. This material could be refolded to an active form, which was purified to homogeneity. A small fraction of the protease was expressed in vivo as a soluble active form, which allowed the monitoring of expression during fermentation by a rapid and simple whole cell assay employing an HIV-1 protease-specific fluorogenic substrate.
Asunto(s)
Escherichia coli/genética , Proteasa del VIH/biosíntesis , Regiones Promotoras Genéticas/genética , Proteínas Recombinantes de Fusión/biosíntesis , Secuencia de Aminoácidos , Arabinosa/genética , Secuencia de Bases , Western Blotting , Escherichia coli/enzimología , Escherichia coli/ultraestructura , Proteasa del VIH/genética , Proteasa del VIH/aislamiento & purificación , Microscopía Electrónica , Datos de Secuencia Molecular , Operón/genética , Plásmidos/genética , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/aislamiento & purificación , Mapeo RestrictivoRESUMEN
The gene coding for the major outer capsid protein (VP7) of simian rotavirus SA-11 has been expressed in a baculovirus-insect cell system. The resulting protein is 35 kDa and is primarily associated with the endoplasmic reticulum. Neutralizing SA-11 polyclonal antiserum and VP7 monospecific antiserum reacted specifically with the expressed gene product. Antiserum derived against the recombinant VP7 protein neutralized SA-11 rotavirus infectivity in a fluorescent focus assay.
Asunto(s)
Baculoviridae/genética , Proteínas de la Cápside , Cápside/genética , Genes Virales , Vectores Genéticos , Rotavirus/genética , Proteínas Estructurales Virales/genética , Animales , Anticuerpos Antivirales/biosíntesis , Antígenos Virales/inmunología , Secuencia de Bases , Cápside/inmunología , Clonación Molecular , ADN Viral/química , Cobayas , Datos de Secuencia Molecular , Mariposas Nocturnas/genética , Pruebas de Neutralización , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Mapeo Restrictivo , Rotavirus/inmunología , Integración ViralRESUMEN
The influence of brain mast cells degranulation, exerted by compound 48/80 given intracerebroventricularly, on the opioid-induced stimulation of the pituitary-adrenal axis, measured indirectly through corticosterone secretion, was investigated in conscious rats. The mu- and delta-opioid receptor agonists Leu-enkephalinamide, morphine and beta-endorphin, given intracerebroventricularly, dose-dependently increased the serum corticosterone levels. The effect of Leu-enkephalinamide was not changed by pretreatment with the histamine H1- and H2-receptor antagonists mepyramine and cimetidine. When Leu-enkephalinamide, morphine and beta-endorphin were given 3 hr after compound 48/80, the serum corticosterone levels were higher than after either one of these drugs given separately, which suggests an independent mechanism of action. In rats pretreated 24 hr earlier with compound 48/80, i.e., when brain mast cells were completely degranulated, the stimulating effect of morphine was almost abolished and the effects of Leu-enkephalinamide and beta-endorphin were considerably reduced. Since the histamine levels in the whole brain and thalamus were elevated 3 and 24 hr after administration of compound 48/80, these results suggest that factors other than histamine depletion from brain mast cells by compound 48/80 may be responsible for the dramatic impairment of the stimulating effect of morphine, Leu-enkephalinamide and beta-endorphin on the pituitary-adrenal axis.
Asunto(s)
Encéfalo/fisiología , Degranulación de la Célula/fisiología , Corticosterona/sangre , Mastocitos/fisiología , Receptores Opioides/fisiología , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Degranulación de la Célula/efectos de los fármacos , Endorfinas/farmacología , Antagonistas de los Receptores Histamínicos/farmacología , Masculino , Morfina/farmacología , Ratas , Ratas Endogámicas , Receptores Opioides/efectos de los fármacos , p-Metoxi-N-metilfenetilamina/farmacologíaRESUMEN
The significance and site of adrenergic receptors involved in the control of the hypothalamic-pituitary-adrenal axis (HPA) activity was assessed indirectly by estimation of serum corticosterone levels 1 h after drug administration to conscious rats. Adrenergic drugs were given intracerebroventricularly (icv) and intraperitoneally (ip), the antagonists 15 min prior to the agonists. Noradrenaline, adrenalin and isoproterenol given by either route increased dose-dependently the serum corticosterone levels. The corticosterone response to icv noradrenaline was almost abolished by icv pretreatment with propranolol, a beta-adrenergic antagonist, and yohimbine, and alpha 2-receptor blocker, and was also considerably reduced by prazosin, an alpha 1-adrenergic antagonist. When given ip, these antagonists did not significantly influence the noradrenaline induced corticosterone response, which suggests a suprapituitary site of action of noradrenaline in stimulation of the HPA. The corticosterone response to icv adrenalin was suppressed by prazosin given by either route. The corticosterone response to ip adrenalin was almost abolished by pretreatment with yohimbine, and also significantly diminished by propranolol given by the same route. The increase in corticosterone secretion, induced by isoproterenol given by either route, was abolished by ip injection of propranolol. These results indicate that noradrenaline stimulates the HPA via alpha- and beta-adrenergic receptors, mainly at the suprapituitary level. Adrenalin increases that activity both via central and pituitary alpha- and beta-adrenoceptors. Isoproterenol activates the HPA by stimulation of pituitary beta-receptors.
Asunto(s)
Corticosterona/sangre , Sistema Hipotálamo-Hipofisario/metabolismo , Sistema Hipófiso-Suprarrenal/metabolismo , Receptores Adrenérgicos alfa/fisiología , Receptores Adrenérgicos beta/fisiología , Agonistas alfa-Adrenérgicos/farmacología , Antagonistas Adrenérgicos alfa/farmacología , Agonistas Adrenérgicos beta/farmacología , Antagonistas Adrenérgicos beta/farmacología , Animales , Catecolaminas/farmacología , Epinefrina/farmacología , Isoproterenol/farmacología , Masculino , Norepinefrina/farmacología , Ratas , Ratas EndogámicasRESUMEN
The effect of brain mast cells degranulation by compound 48/80 on the pituitary-adrenocortical activity, measured indirectly through corticosterone secretion, and the involvement of a histaminergic mechanism in that stimulation was investigated in conscious rats. All the drugs were given intracerebroventricularly (icv), histamine antagonists 15 min prior to compound 48/80. Compound 48/80 induced a significant dose- and time-related increase in the serum corticosterone levels. That increase, measured 1 h after administration of compound 48/80, was moderately diminished by icv pretreatment of rats with mepyramine and cimetidine, histamine H1- and H2-receptor antagonists. Three hours after administration of compound 48/80 mast cells of the thalamus and the hypothalamus were completely degranulated. At the same time the thalamus and the whole brain histamine levels were substantially higher than in the saline-treated control rats. The above results suggest that histamine liberated from the brain mast cells and central histamine receptors play a moderate role in increasing the pituitary-adrenocortical activity by compound 48/80.
Asunto(s)
Corteza Suprarrenal/fisiología , Hipófisis/fisiología , p-Metoxi-N-metilfenetilamina/farmacología , Corteza Suprarrenal/efectos de los fármacos , Animales , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Cimetidina/farmacología , Corticosterona/metabolismo , Gránulos Citoplasmáticos/fisiología , Histamina/metabolismo , Hipotálamo/citología , Hipotálamo/efectos de los fármacos , Cinética , Masculino , Mastocitos/ultraestructura , Hipófisis/efectos de los fármacos , Pirilamina/farmacología , Ratas , Ratas Endogámicas , Tálamo/citología , Tálamo/efectos de los fármacos , Tálamo/metabolismoRESUMEN
The effect of inhibition of brain histamine synthesis by alpha-fluoromethylhistidine (alpha-FMH) on the pituitary adrenocortical activity stimulated by D-Ala-D-Leu-enkephalinamide (DADL) and morphine was investigated indirectly through corticosterone secretion in conscious rats. alpha-FMH (20 mg/kg i.p.) drastically reduced the whole brain histamine content, measured 2 h later. The same pretreatment also considerably reduced the corticosterone response to morphine given intraperitoneally. When alpha-FMH was administered intracerebroventricularly (50 micrograms), the maximum inhibition of the corticosterone response to DADL and morphine occurred 4 h after administration, which may suggest a weaker accessibility of alpha-FMH from the cerebral ventricle to the brain structures involved in pituitary-adrenocortical stimulation. The corticosterone responses were not related to the core temperature changes. These results indicate that inhibition of brain histamine synthesis by alpha-FMH considerably impairs the pituitary-adrenocortical response to the opioid delta- and mu-receptor agonists DADL and morphine. They also suggest that neuronal histamine is significantly involved in the central stimulation of the pituitary-adrenal axis by opioids.
Asunto(s)
Corticosterona/metabolismo , Encefalina Leucina/análogos & derivados , Liberación de Histamina/efectos de los fármacos , Histidina Descarboxilasa/farmacología , Metilhistidinas/farmacología , Morfina/farmacología , Animales , Temperatura Corporal/efectos de los fármacos , Temperatura Corporal/fisiología , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Corticosterona/sangre , Encefalina Leucina/farmacología , Leucina Encefalina-2-Alanina/análogos & derivados , Leucina Encefalina-2-Alanina/farmacología , Masculino , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Sistema Hipófiso-Suprarrenal/fisiología , Ratas , Ratas Endogámicas , Receptores Opioides/efectos de los fármacos , Receptores Opioides/fisiología , Receptores Opioides delta , Receptores Opioides muRESUMEN
The involvement of brain histamine, contained in mast cells and neurons, and central histamine receptors in stimulation of the pituitary-adrenal axis by opioids was investigated indirectly through corticosterone secretion in conscious rats. The opioid agonists leu-enkephalinamide (DADL), morphine and b-endorphin (b-End) the s- m- and putative e-opioid receptor agonists, given intracerebroventricularly (ici) induced a significant, dose-dependent increase in serum corticosterone levels. The corticosterone response to b-End and morphine was significantly impaired by pretreatment with mepyramine and cimetidine, whereas the response to DADL was insensitive to histamine antagonists. Twenty four hours after administration of compound 48/80 the corticosterone responses to the opioids were greatly diminished. Pretreatment with a-fluoromethylhistidine (a-FMH), a histamine synthesis inhibitor, almost abolished the corticosterone response to DADL, b-End and morphine. These results indicate that central neuronal histamine and histamine receptors are significantly involved in the opioid-induced stimulation of the pituitary-adrenal axis in rats.
Asunto(s)
Corteza Suprarrenal/fisiología , Encéfalo/fisiología , Endorfinas/farmacología , Histamina/fisiología , Hipófisis/fisiología , Receptores Histamínicos/fisiología , Corteza Suprarrenal/efectos de los fármacos , Animales , Cimetidina/farmacología , Corticosterona/sangre , Leucina Encefalina-2-Alanina/análogos & derivados , Leucina Encefalina-2-Alanina/farmacología , Histamina/análogos & derivados , Histamina/farmacología , Histidina Descarboxilasa/antagonistas & inhibidores , Masculino , Morfina/farmacología , Hipófisis/efectos de los fármacos , Pirilamina/farmacología , Ratas , Ratas Endogámicas , betaendorfina/farmacología , p-Metoxi-N-metilfenetilamina/farmacologíaRESUMEN
Involvement of a central histaminergic mechanism in the stimulating effect of beta-endorphin (beta-End) on the pituitary-adrenocortical activity, measured indirectly through corticosterone secretion, was investigated in conscious rats. The rise in serum corticosterone levels, induced by beta-End injected intraventricularly (icv) was considerably impaired by pretreatment with naltrexone, an opioid receptor antagonist. The stimulating effect of beta-End was almost totally suppressed by a prior icv administration of mepyramine, a histamine H1-receptor antagonist, and also considerably reduced by pretreatment with cimetidine, an H2-receptor antagonist. The strongest suppression, by 83%; of the beta-End-induced corticosterone response was evoked by a prior administration of alpha-fluoromethylhistidine, an inhibitor of neuronal histamine synthesis in the brain. These results indicate that both the brain neuronal histamine and central histamine H1- and H2-receptors are considerably involved in the beta-endorphin-induced stimulation of the pituitary-adrenocortical activity.
Asunto(s)
Corticosterona/metabolismo , Antagonistas de los Receptores Histamínicos/farmacología , Histamina/análogos & derivados , betaendorfina/farmacología , Animales , Encéfalo/metabolismo , Corticosterona/sangre , Histamina/biosíntesis , Histamina/farmacología , Inyecciones Intraventriculares , Masculino , Naltrexona/farmacología , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Sistema Hipófiso-Suprarrenal/metabolismo , Sistema Hipófiso-Suprarrenal/fisiología , Ratas , Ratas Endogámicas , Receptores Histamínicos/fisiología , betaendorfina/administración & dosificaciónRESUMEN
A two-fold (C2) symmetric inhibitor of the protease of human immunodeficiency virus type-1 (HIV-1) has been designed on the basis of the three-dimensional symmetry of the enzyme active site. The symmetric molecule inhibited both protease activity and acute HIV-1 infection in vitro, was at least 10,000-fold more potent against HIV-1 protease than against related enzymes, and appeared to be stable to degradative enzymes. The 2.8 angstrom crystal structure of the inhibitor-enzyme complex demonstrated that the inhibitor binds to the enzyme in a highly symmetric fashion.
Asunto(s)
Endopeptidasas/metabolismo , Productos del Gen pol/metabolismo , VIH-1/enzimología , Inhibidores de Proteasas/farmacología , Alcoholes del Azúcar/farmacología , Valina/análogos & derivados , Secuencia de Aminoácidos , Sitios de Unión , Diseño de Fármacos , Proteasa del VIH , Cinética , Modelos Moleculares , Datos de Secuencia Molecular , Conformación Proteica , Valina/farmacologíaRESUMEN
A procedure is described which employs pepstatin-agarose for the affinity purification of either HIV-1 or HIV-2 protease from two similar recombinant E. coli constructs that were developed for the expression of these enzymes. HIV-2 protease was routinely expressed at much higher levels than the HIV-1 enzyme and pepstatin-agarose was the only chromatography step required to isolate pure HIV-2 protease from crude bacterial lysates. A Mono S ionic exchange step following pepstatin-agarose chromatography was sufficient to bring the HIV-1 protease to homogeneity. Purification of either enzyme can be completed in several days yielding homogeneous preparations suitable for crystallization and other physical characterization.
Asunto(s)
Endopeptidasas/aislamiento & purificación , Productos del Gen pol/aislamiento & purificación , VIH-1/enzimología , VIH-2/enzimología , Cromatografía de Afinidad , Endopeptidasas/genética , Escherichia coli , Productos del Gen pol/genética , Proteasa del VIH , Peso Molecular , Pepstatinas , Proteínas Recombinantes/aislamiento & purificaciónRESUMEN
A site of action of adrenergic drugs and type of receptors involved in stimulating the pituitary-adrenocortical activity, assessed indirectly through corticosterone (CS) secretion, was investigated in conscious rats. Adrenergic drugs were administered intraperitoneally (i.p.) or intracerebroventricularly (i.c.v.), the antagonists always 15 min prior to the agonist and 1 h later the trunk blood was collected for CS determination. Phenylephrine (PHE) (alpha 1-agonist) given by either route increased dose-dependently the serum CS levels. Such effect of PHE given i.p. was abolished by i.p. pretreatment with prazosin (PRA) (alpha 1-antagonist), and similar effect of i.c.v. administered PHE was considerably suppressed by i.c.v. pretreatment with PRA. I.c.v. pretreatment with yohimbine (YO) (alpha 2-antagonist), did not influence the effect of PHE. Clonidine (CLON) given i.c.v. significantly increased the serum CS level and such effect was halved by i.c.v. pretreatment with either YO and PRA. I.p. administered PRA did not decrease the CLON-induced CS response. YO given i.p. considerably reduced the CLON-induced CS response in both low and high doses thus indicating the interaction with pre- and post-synaptic alpha-adrenoceptors. These results suggest that PHE activated the pituitary-adrenocortical axis by a selective stimulation of alpha 1-adrenoceptors located in the hypothalamus and possibly on anterior pituitary corticotrophs. CLON seems to stimulate the secretion of CS by activating both alpha 2- and alpha 1-adrenoceptors in the hypothalamus.