RESUMEN
The present study correlates the severity of dementia in Alzheimer's disease with the degree of neuropathology present in the nucleus basalis of Meynert. We assessed neurofibrillary tangles, neuronal loss and morphometric changes in 21 patients with Alzheimer's disease who underwent extensive neuropsychological testing before death. We report a highly significant correlation between scores in the psychological tests and all of the neuropathological markers examined within the nucleus basalis of Meynert. The test that correlated most closely with these morphological measures was Folstein's Mini Mental State. Among the different neuropathological changes, the number of neurofibrillary tangles was strongly correlated with the degree of dementia. We also provide evidence for a differential involvement of the three subdivisions of the nucleus basalis in Alzheimer's disease neuropathology. The posterior subdivision, which provides a substantial cholinergic input to the parahippocampal gyrus, was the more profoundly affected. Taken together, these results point to an important participation of the nucleus basalis in dementia of the Alzheimer type. In addition, the strong correlation between neuropathological changes and neuropsychological scores indicates the reliability of these tests in assessing the progression of the disease.
Asunto(s)
Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/psicología , Sustancia Innominada/patología , Anciano , Anciano de 80 o más Años , Recuento de Células , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ovillos Neurofibrilares/patología , Neuronas/patología , Pruebas NeuropsicológicasRESUMEN
The effects of midazolam on the dorso- and ventromedial nuclei of the hypothalamus, administered during 120 days via gastric intubation, was studied in two groups of Wistar rats. The rats (50) of one of the groups were 2 months old, and those of the other (50) 24 months, 20 rats of both groups received 1 mg/kg of midazolam, and the other 20, 3 mg/kg As controls 20 rats of the same strain and age (10 for each group) received only saline. Neuronal count and karyometry did not revealed significant differences between controls and experimental rats. Only the group of old rats showed a slight increase in the number of dark neurons, with a decrease in the karyometric index.
Asunto(s)
Benzodiazepinas/toxicidad , Hipotálamo/efectos de los fármacos , Midazolam/toxicidad , Degeneración Nerviosa/inducido químicamente , Factores de Edad , Animales , Benzodiazepinas/administración & dosificación , Biomarcadores , Recuento de Células/efectos de los fármacos , Núcleo Celular/efectos de los fármacos , Midazolam/administración & dosificación , Proteínas del Tejido Nervioso/análisis , Neuronas/efectos de los fármacos , Parvalbúminas/análisis , Ratas , Ratas WistarAsunto(s)
Ansiedad/psicología , Existencialismo , Altruismo , Actitud Frente a la Muerte , Miedo , Humanos , Religión , Alienación SocialAsunto(s)
Política de Salud , Prioridades en Salud , Apoyo a la Investigación como Asunto , Investigación/estadística & datos numéricos , Percepción Social , Síndrome de Inmunodeficiencia Adquirida/economía , Síndrome de Inmunodeficiencia Adquirida/mortalidad , Síndrome de Inmunodeficiencia Adquirida/prevención & control , Adulto , Altruismo , Actitud Frente a la Salud , Países en Desarrollo/economía , Diarrea Infantil/economía , Diarrea Infantil/mortalidad , Diarrea Infantil/prevención & control , Humanos , Lactante , Malaria/economía , Malaria/mortalidad , Malaria/prevención & control , Estados UnidosRESUMEN
The effects of midazolam (MDZ) treatment during 120 days have been studied in 2 groups of young and old Wistar rats: (50 animals two months, 50 aged 24 months). 20 rats of both groups got 1 mg/kg of MDZ daily, 20 3 mg/kg, and finally 10, animals 1 ml saline all administered by gastric intubation. The general effects of MDZ (mortality, weight changes and memory of an aversive stimuli showed no significant differences with the controls either in young or old rats. In the hippocampus, the total count of neurons gave no significant differences compared to controls. However, in the group of old rats a higher number of dark and pycnotic cells, principally in those rats treated with 3 mg/kg of MDZ was observed. The global area of the CA1, CA4 fields and of the GD was significant reduced in comparison with the controls. These results favour the conclusion that the MDZ has a minimal neurotoxicity: only the group of old rats treated with 3 mg/kg showed weak signs of hippocampal effects.
Asunto(s)
Ansiolíticos/farmacología , Hipocampo/efectos de los fármacos , Hipnóticos y Sedantes/farmacología , Midazolam/farmacología , Administración Oral , Factores de Edad , Animales , Ansiolíticos/administración & dosificación , Ansiolíticos/toxicidad , Reacción de Prevención/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Núcleo Celular , Giro Dentado/efectos de los fármacos , Giro Dentado/ultraestructura , Relación Dosis-Respuesta a Droga , Hipocampo/ultraestructura , Hipnóticos y Sedantes/administración & dosificación , Hipnóticos y Sedantes/toxicidad , Memoria/efectos de los fármacos , Midazolam/administración & dosificación , Midazolam/toxicidad , Neuronas/efectos de los fármacos , Neuronas/ultraestructura , Ratas , Ratas WistarRESUMEN
Hepatic encephalopathy is mainly caused by an excess of ammonium ions. Among other effects, glutamate transmission in the brain is impaired, and thereof, neuronal function in multiple systems is affected. We investigated in rats the effect of diet induced hyperammonemia in the entorhinal cortex, a well known glutamatergic pathway to the dentate gyrus, by measuring the neuronal nuclear area in two entorhinal cortex subfields (dorsolateral subfield (DLE) and dorsal intermediate subfield (DIE); [Insausti, R., Herrero, M.T. and Witter, M.P., Origin and distribution of cortical efferents from the entorhinal cortex in the rat, Hippocampus, 7 (1997) 146-183]) that project to separate septotemporal levels of the hippocampus. After 2, and more overtly, after 8 weeks of the ammonium enriched diet consumption, the neuronal nuclear size in layers II, III, V and VI of both entorhinal cortex subfields showed a significant reduction in size. We conclude that already at 2 weeks of treatment there is a decrease in neuronal nuclear size in all layers of the entorhinal cortex, which might have widespread functional effects on cortical and subcortical structures.
