| 1. |
- Dahlqvist, Per, et al.
(författare)
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Environmental enrichment reverses learning impairment in the Morris water maze after focal cerebral ischemia in rats
- 2004
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Ingår i: European Journal of Neuroscience. - 0953-816X .- 1460-9568. ; 19:8, s. 2288-2298
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Tidskriftsartikel (refereegranskat)abstract
- Cognitive impairment is common after ischemic stroke. In rodent stroke models using occlusion of the middle cerebral artery (MCA) this is reflected by impaired spatial memory associated with the size of the ischemic lesion. Housing in an enriched environment enhances brain plasticity and improves recovery of sensorimotor functions after experimental stroke in rats. In this study we report that postischemic housing in an enriched environment also attenuates the long-term spatial memory impairment after MCA occlusion and extinguishes the association between spatial memory and infarct volume. An enriched environment did not significantly alter the expression of selected neuronal plasticity-associated genes 1 month after MCA occlusion, indicating that most of the adaptive changes induced by an enriched environment have already occurred at this time point. We conclude that the attenuated memory impairment induced by environmental enrichment after MCA occlusion provides a useful model for further studies on the neurobiological mechanisms of recovery of cognitive functions after ischemic stroke.
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| 2. |
- Gussing, Fredrik, et al.
(författare)
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NQO1 activity in the main and the accessory olfactory systems correlates with the zonal topography of projection maps
- 2004
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Ingår i: European Journal of Neuroscience. - : Wiley-Blackwell. - 0953-816X .- 1460-9568. ; 19:9, s. 2511-2518
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Tidskriftsartikel (refereegranskat)abstract
- The mouse olfactory epithelium (OE) is divided into spatial zones, each containing neurons expressing zone-specific subsets of odorant receptor genes. Likewise, the vomeronasal (VN) organ is organized into apical and basal subpopulations of neurons expressing different VN receptor gene families. Axons projecting from the different OE zones and VN subpopulations form synapses within circumscribed regions in the glomerular layer of the olfactory bulb (OB) and accessory olfactory bulb (AOB), respectively. We here show that mature neurons in one defined zone selectively express NADPH:quinone oxidoreductase (NQO1), an enzyme that catalyses reduction of quinones. Immunohistochemistry and in situ hybridization analyses show non-overlapping expression of NQO1 and the Rb8 neural cell adhesion molecule (RNCAM/OCAM) in OE and axon terminals within glomeruli of the OB. In addition, NQO1 immunoreactivity reveals selective, zone-specific axon fasciculation in the olfactory nerve. VN subpopulations do not show complementary patterns of RNCAM and NQO1 immunoreactivity, instead both genes are co-expressed in apical VN neurons that project to the rostral AOB. These results indicate that one division of both the accessory and the main olfactory projection maps are composed of sensory neurons that are specialized to reduce environmental and/or endogenously produced quinones via an NQO1-dependent mechanism. The role of NQO1 in bioactivation of quinoidal drugs also points to a connection between zone-specific NQO1 expression and zone-specific toxicity of certain olfactory toxins.
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| 3. |
- Westberg, Karl-Gunnar, et al.
(författare)
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Discharge patterns of neurons in the medial pontobulbar reticular formation during fictive mastication in the rabbit
- 2001
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Ingår i: European Journal of Neuroscience. - : Wiley-Blackwell. - 0953-816X .- 1460-9568. ; 14:10, s. 1709-1718
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Tidskriftsartikel (refereegranskat)abstract
- In this study, we describe functional characteristics of neurons forming networks generating oral ingestive motor behaviours. Neurons in medial reticular nuclei on the right side of the brainstem between the trigeminal and hypoglossal motor nuclei were recorded in anaesthetized and paralysed rabbits during two types of masticatory-like motor patterns induced by electrical stimulation of the left (contralateral) or right (ipsilateral) cortical masticatory areas. Sixty-seven neurons in nucleus reticularis pontis caudalis (nPontc), nucleus reticularis parvocellularis (nParv), and nucleus reticularis gigantocellularis (Rgc) were studied. These were classified as phasic or tonic depending on their firing pattern during the fictive jaw movement cycle. Phasic neurons located in the dorsal part of nPontc were active during the jaw opening phase, whilst those in dorsal nParv tended to fire during the closing phase. In most neurons, burst duration and firing frequency changed between the two motor patterns, but there was little change in phase of firing. Tonic units were mainly recorded in the ventral half of nPontc, and at the junction between Rgc and caudal nParv. Cortical inputs with short latency from the contralateral masticatory area were more frequent in phasic (82%) than tonic (44%) neurons, whilst inputs from the ipsilateral cortex were equal in the two subgroups (57% and 56%). Phasic neurons had significantly shorter mean contralateral than ipsilateral cortical latencies, whilst there was no difference among tonic neurons. Intra- and perioral primary afferent inputs activated both types of neurons at oligo-synaptic latencies. Our results show that subpopulations of neurons in medial reticular nuclei extending from the caudal part of the trigeminal motor nucleus to the rostral third of the hypoglossal motor nucleus are active during the fictive masticatory motor behaviour. Unlike masticatory neurons in the lateral tegmentum, the medial subpopulations are spatially organized according to discharge pattern.
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| 4. |
- Athanassiadis, Tuija, 1971-, et al.
(författare)
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Physiological characterization, localization and synaptic inputs of bursting and nonbursting neurons in the trigeminal principal sensory nucleus of the rat
- 2005
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Ingår i: European Journal of Neuroscience. - : Wiley. - 0953-816X .- 1460-9568. ; 22:12, s. 3099-3110
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Tidskriftsartikel (refereegranskat)abstract
- A population of neurons in the trigeminal principal sensory nucleus (NVsnpr) fire rhythmically during fictive mastication induced in the in vivo rabbit. To elucidate whether these neurons form part of the central pattern generator (CPG) for mastication, we performed intracellular recordings in brainstem slices taken from young rats. Two cell types were defined, nonbursting (63%) and bursting (37%). In response to membrane depolarization, bursting cells, which dominated in the dorsal part of the NVsnpr, fired an initial burst followed by single spikes or recurring bursts. Non-bursting neurons, scattered throughout the nucleus, fired single action potentials. Microstimulation applied to the trigeminal motor nucleus (NVmt), the reticular border zone surrounding the NVmt, the parvocellular reticular formation or the nucleus reticularis pontis caudalis (NPontc) elicited a postsynaptic potential in 81% of the neurons tested for synaptic inputs. Responses obtained were predominately excitatory and sensitive to glutamatergic antagonists DNQX and/or APV. Some inhibitory and biphasic responses were also evoked. Bicuculline methiodide or strychnine blocked the IPSPs indicating that they were mediated by GABA(A) or glycinergic receptors. About one-third of the stimulations activated both types of neurons antidromically, mostly from the masseteric motoneuron pool of NVmt and dorsal part of NPontc. In conclusion, our new findings show that some neurons in the dorsal NVsnpr display both firing properties and axonal connections which support the hypothesis that they may participate in masticatory pattern generation. Thus, the present data provide an extended basis for further studies on the organization of the masticatory CPG network.
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| 5. |
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| 6. |
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| 7. |
- Estévez-Silva, Héctor M., et al.
(författare)
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Pridopidine modifies disease phenotype in a SOD1 mouse model of amyotrophic lateral sclerosis
- 2022
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Ingår i: European Journal of Neuroscience. - : John Wiley & Sons. - 0953-816X .- 1460-9568. ; 55:5, s. 1356-1372
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Tidskriftsartikel (refereegranskat)abstract
- Amyotrophic lateral sclerosis (ALS) is a lethal and incurable neurodegenerative disease due to the loss of upper and lower motor neurons, which leads to muscle weakness, atrophy, and paralysis. Sigma-1 receptor (σ-1R) is a ligand-operated protein that exhibits pro-survival and anti-apoptotic properties. In addition, mutations in its codifying gene are linked to development of juvenile ALS pointing to an important role in ALS. Here, we investigated the disease-modifying effects of pridopidine, a σ-1R agonist, using a delayed onset SOD1 G93A mouse model of ALS. Mice were administered a continuous release of pridopidine (3.0 mg/kg/day) for 4 weeks starting before the appearance of any sign of muscle weakness. Mice were monitored weekly and several behavioural tests were used to evaluate muscle strength, motor coordination and gait patterns. Pridopidine-treated SOD1 G93A mice showed genotype-specific effects with the prevention of cachexia. In addition, these effects exhibited significant improvement of motor behaviour 5 weeks after treatment ended. However, the survival of the animals was not extended. In summary, these results show that pridopidine can modify the disease phenotype of ALS-associated cachexia and motor deficits in a SOD1 G93A mouse model.
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| 8. |
- Green, P G, et al.
(författare)
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Role of adrenal medulla in development of sexual dimorphism in inflammation
- 2001
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Ingår i: European Journal of Neuroscience. - 0953-816X .- 1460-9568. ; 14, s. 1436-1444
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Tidskriftsartikel (refereegranskat)abstract
- Many inflammatory diseases show a female predilection in adults, but not prepubertally. Because sex differences in the inflammatory response in the adult rat are mediated, in part, by sexual dimorphism in adrenal medullary function, we investigated the contribution of the adrenal medulla to the ontogeny of sexual dimorphism in inflammation. Whilst there was no sex difference in the magnitude of the plasma extravasation (PE) induced by the potent inflammatory mediator bradykinin (BK) in prepubertal rats, in adult rats BK-induced PE was markedly greater in males. Also, adult male rats, gonadectomized prior to puberty, had a lower magnitude of BK-induced PE than did adult male controls, whilst adult females gonadectomized prepubertally had higher BK-induced PE than did controls. In rats gonadectomized after puberty, the magnitude of BK-induced PE in adult males was not affected, whilst in females it resulted in significantly higher BK-induced PE, similar to the effect of prepubertal gonadectomy. When tested prepubertally, adrenal denervation increased the magnitude of BK-induced PE in females, but not in males. In contrast, in both males and females tested as adults, but castrated prepubertally, and in gonad-intact adult females, adrenal denervation significantly increased the magnitude of BK-induced PE. Adrenal denervation in prepubertal females given adult levels of 17 beta -oestradiol produced a marked enhancement in the denervation-induced increase in magnitude of BK-induced PE compared to females not exposed prematurely to sex hormones. These studies suggest that an adrenal medulla-dependent inhibition of BK-induced PE is present in female but not male rats, and is enhanced by oestrogen but suppressed by testosterone.
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| 9. |
- Hariz, Marwan I, et al.
(författare)
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Gilles de la Tourette syndrome and deep brain stimulation
- 2010
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Ingår i: European Journal of Neuroscience. - : Wiley. - 0953-816X .- 1460-9568. ; 32:7, s. 1128-1134
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Tidskriftsartikel (refereegranskat)abstract
- Gilles de la Tourette Syndrome (GTS) is characterized by multiple motor and one or more vocal/phonic tics. Psychopathology and co-morbidity occur in approximately 80-90% of clinical cohorts. The most common psychopathologies are attention deficit hyperactivity disorder, obsessive-compulsive behaviours, obsessive-compulsive disorder, depression, anxiety and certain behavioural disorders. In severe GTS patients who are refractory to medication and other therapies, deep brain stimulation (DBS) is investigated. To date there have been some 50-55 patients who have received DBS in 19 centres worldwide. Nine different brain targets in the thalamus, the pallidum, and the ventral caudate and anterior internal capsule have been stimulated. This paper reviews critically and in detail all studies published to date. Only two studies on just a few patients fulfil some of the evidence-based criteria. DBS for GTS is therefore still highly experimental.
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| 10. |
- Hu, Xiao-Lei, et al.
(författare)
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Dynamic changes of the anti- and pro-apoptotic proteins Bcl-w, Bcl-2, and Bax with Smac/Diablo mitochondrial release after photothrombotic ring stroke in rats
- 2004
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Ingår i: European Journal of Neuroscience. - : Wiley-Blackwell. - 0953-816X .- 1460-9568. ; 20:5, s. 1177-1188
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Tidskriftsartikel (refereegranskat)abstract
- The anti‐apoptotic proteins Bcl‐w and Bcl‐2 and the pro‐apoptotic protein Bax may mediate cell death or survival via regulation of the mitochondria including second mitochondria‐derived activator of caspase (Smac)/direct inhibitor of apoptosis protein (IAP)‐binding protein with low pI (DIABLO) release. This study aimed to explore alterations in Bcl‐w, Bcl‐2, and Bax and the relationship between these proteins and Smac/DIABLO by means of in situ hybridization, immunohistochemical (IHC) staining, and Western blots after low‐ and high‐intensity photothrombotic ring stroke. At 4 h after low‐intensity irradiation, we found widespread bcl‐w overexpression on both the mRNA and protein levels in the bilateral cortex except the ring lesion region and in subcortical regions. A prolonged elevation of Bcl‐2 with relatively unchanged Bax in the mitochondrial fraction was demonstrated from 4 to 72 h. These upregulated anti‐apoptotic proteins combined with little Smac/DIABLO release might be associated with increased cell survival and thereby remarkable morphological recovery after low‐intensity irradiation. After high‐intensity irradiation, we observed decreased bcl‐w and bcl‐2 mRNA with increased Bcl‐2 protein in the cytosolic fraction, whereas the Bax protein remained in scattered ischaemic cells in the ring lesion and the region at risk that corresponded with release of Smac/DIABLO from mitochondria to the cytosol at 1–24 h. These changes might be related to the massive cell death observed after high‐intensity irradiation. Taken together, the balance and the location of anti‐apoptotic proteins vs. pro‐apoptotic proteins could be associated with the translocation of Smac/DIABLO from the mitochondria to the cytosol and therefore closely related to cell death or survival after focal cerebral ischaemia.
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