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Intracerebral microdialysis as a tool to monitor transmitter release from grafted cholinergic and monoaminergic neurons

In the present study the microdialysis technique has been used as a tool for the study of functional regulation of intracerebrally grafted cholinergic and monoaminergic neurons as well as for the analysis of graft-host interactions. Fetal noradrenergic, serotonergic, dopaminergic, and cholinergic neurons were transplanted into the hippocampus or striatum previously denervated of their intrinsic mo

Amelioration of spatial memory impairment by intrahippocampal grafts of mixed septal and raphe tissue in rats with combined cholinergic and serotonergic denervation of the forebrain

Previous studies in the rat have shown that a serotonergic depletion greatly potentiates the learning and memory impairments produced by pharmacological or lesion-induced cholinergic blockade in the forebrain. The impairment produced by combined serotonergic-cholinergic lesions is reminiscent of that seen in memory-impaired aged rats. In the present experiment, we investigated whether grafts of ch

Acetylcholine release from intrahippocampal septal grafts is under control of the host brain

The activity of intrahippocampal transplants of cholinergic neurons was monitored by microdialysis in awake, freely moving rats. Fetal septal-diagonal band tissue was implanted into rats with a complete transection of the fimbria-fornix cholinergic pathway either as a cell suspension injected into the hippocampus or as a solid graft implanted in the lesion cavity. The grafts restored baseline acet

Synaptic connections formed by grafts of different types of cholinergic neurons in the host hippocampus

The present experiment was performed to determine whether different types of grafted central cholinergic neurons are able to form synaptic contacts with host hippocampal neurons. Grafts from the septal-diagonal band area, which contain the neurons that normally innervate the hippocampal formation, were compared to those from the nucleus basalis magnocellularis region (NBM), the striatum, the ponto

Acetylcholine release in the rat hippocampus as studied by microdialysis is dependent on axonal impulse flow and increases during behavioural activation

Changes in extracellular levels of acetylcholine and choline in the hippocampal formation were measured using intracerebral microdialysis coupled to high performance liquid chromatography with post-column enzyme reaction and electrochemical detection. Various pharmacological and physiological manipulations were applied to awake unrestrained normal rats and rats subjected to a cholinergic denervati

Reafferentation of the subcortically denervated hippocampus as a model for transplant-induced functional recovery in the CNS

Subcortical deafferentation of the hippocampal formation is known to induce profound behavioural deficits. Transplants of fetal septal or brainstem tissue are capable of restoring some aspects of normal physiological and behavioural function in subcortically deafferented (i.e. fimbria-fornix or septal lesioned) rats. Such grafts have been shown to re-establish extensive new afferent inputs to the

Multiphase transport model of swelling cellulose based materials with variable hydrophobicity

A thermodynamically consistent model for multiphase flow in swelling cellulose based material is adopted. The material is decomposed into a fiber phase, a gas phase and an inter-fiber water phase, where the fiber phase consists of a fiber water and a dry fiber constituent and the gas phase is an ideal gas mixture of water vapor and dry air. The model is derived within mixture theory and includes l

Combined cholinergic and serotonergic denervation of the forebrain produces severe deficits in a spatial learning task in the rat

The purpose of the present experiments was to study the effects of a combined cholinergic and serotonergic denervation of the rat forebrain on spatial learning using the Morris water maze task. Experiment 1 compared the acute effects of a radiofrequency lesion of the septum, an intraventricular 5,7-dihydroxytryptamine (5,7-DHT) lesion, and a combined septal plus 5,7-DHT lesion. Although the 5,7-DH

Comparison of growth and reinnervation properties of cholinergic neurons from different brain regions grafted to the hippocampus

Grafts of five different types of central cholinergic neurons, from the septal-diagonal band region, the nucleus basalis magnocellularis region (NBM), the striatum, the pontomesencephalic tegmentum of the brainstem, and the spinal cord, were compared with respect to their ability to grow and to reinnervate the cholinergically denervated hippocampal formation of adult rats. The areas were dissected

Electrophysiological and pharmacological properties of neurons within solid basal forebrain transplants in the rat brain

Electrophysiological and pharmacological properties of neurons within solid basal forebrain transplants were studied in adult rats anesthetized with urethane. No specific topography of the neurons recorded was observed within the graft. The mean spontaneous activity of the grafted neurons (GNs) was relatively low (4.9 impulses/s) but not unlike that of other central neurons in situ. A large propor

Spatial learning and memory following fimbria-fornix transection and grafting of fetal septal neurons to the hippocampus

The ability of intrahippocampal grafts of fetal septal-diagonal band tissue, rich in developing cholinergic neurons, to ameliorate cognitive impairments induced by bilateral fimbria-fornix transections in rats was examined in three experiments using the Morris water-maze to test different aspects of spatial memory. Experiment 1. Rats with fimbriafornix lesions received either septal cell suspensio

Grafted septal neurons form cholinergic synaptic connections in the dentate gyrus of behaviorally impaired aged rats

A group of aged, behaviorally impaired rats received suspension grafts of fetal septal-diagonal band tissue into the otherwise intact hippocampal formation. Three months after grafting, behaviorally recovered rats were studied by immunocytochemistry by using monoclonal antibodies to choline acetyltransferase (ChAT) and electron microscopy. The innervation of the host dentate gyrus by graft-derived

Behavioural effects of human fetal dopamine neurons grafted in a rat model of Parkinson's disease

The ventral mesencephalon, containing the developing dopaminergic neurons of the substantia nigra-ventral tegmental region, was obtained from aborted human fetuses of 9-19 weeks of gestation. The tissue was grafted into the striatum of rats previously subjected to a 6-hydroxydopamine lesion of the mesostriatal dopamine pathway. The graft recipients were immunosuppressed by daily injections of Cycl

Cyclosporin A increases survival of cross-species intrastriatal grafts of embryonic dopamine-containing neurons

The survival and function of cross-species (mouse-to-rat) grafts of fetal mesencephalic dopamine (DA) neurons, implanted as a cell suspension in the striatum of rats with lesions of the mesostriatal DA system, have been studied in animals with and without immunosuppression induced by Cyclosporin A (CyA). At 6 weeks after grafting 3 out of 7 non-CyA treated animals showed some degree of graft survi

Material Differentiations of Territoriality in Spaces of Consumption - Case studies of open-air markets in London

The aim of the paper is to investigate how material form and territorial complexity support and differentiate social interaction in urban consumption spaces. Spaces of consumption may well be the most socially mixed spaces in modern cities. Open-air markets provide excellent conditions to study these issues since they represent a broad, and often condensed, range of public situations in a consumpt

Human fetal dopamine neurons grafted in a rat model of Parkinson's disease : ultrastructural evidence for synapse formation using tyrosine hydroxylase immunocytochemistry

Human fetal mesencephalic dopamine (DA) neurons, obtained from 6.5-9 week old aborted fetuses, were grafted to the striatum of immunosuppressed rats with 6-hydroxydopamine lesions of the ascending mesostriatal DA pathway. The effects on amphetamine-induced motor asymmetry were studied at various timepoints after grafting. At eight weeks, functional graft effects were not evident but after 11 weeks