| 1. |
- Risedal, Anette, et al.
(författare)
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Environmental influences on functional outcome after a cortical infarct in the rat.
- 2002
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Ingår i: Brain Research Bulletin. - 0361-9230 .- 1873-2747. ; 58:3, s. 315-321
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Tidskriftsartikel (refereegranskat)abstract
- The effect of postoperative housing conditions on functional outcome and brain-derived neurotrophic factor (BDNF) gene expression was evaluated 1 month after a distal ligation of the right middle cerebral artery (MCA) in spontaneously hypertensive rats. Two days postoperatively the rats were randomized into four groups; individually housed with no equipment (deprived group), individually housed with free access to a connected running wheel (running group), housed together in a large cage with no equipment (social group) or in the same size of cage furnished with bars, chains and various things to manipulate (enriched group). The enriched rats had significantly higher scores when crossing a rotating horizontal rod than deprived and running rats. The social group performed significantly better than the deprived group. The BDNF gene expression in the ipsi- and contralateral cortex, thalamus, hippocampus and cerebellum did not significantly differ between the groups. The weight of the adrenal glands was significantly increased in running rats suggesting that postischemic running may be stressful. We conclude that the beneficial effect of postischemic environmental enrichment is likely to be a combination of social and various physical activities, and that BDNF gene expression 1 month after a cortical infarct did not correlate with functional outcome.
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| 2. |
- Bergenius, J., et al.
(författare)
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The subjective horizontal at different angles of roll-tilt in patients with unilateral vestibular impairment
- 1996
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Ingår i: Brain Research Bulletin. - : Elsevier BV. - 0361-9230 .- 1873-2747. ; 40:5-6, s. 385-390
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Tidskriftsartikel (refereegranskat)abstract
- The subjective visual horizontal is mainly dependent on the otolithic system. A group of 11 patients with sudden unilateral vestibular impairment were asked to set a dimly illuminated bar according to their subjective horizontal when they were seated upright and tilted 10, 20, and 30 degrees to the right and left in a completely darkened room (Bias test). The patients were examined within 1 week, after 3 and 6 weeks, and 9 patients consented to the 11-week follow-up. The results were compared with ENG examinations. In the acute stage of the disease all patients, when they were in upright position, set the light bar tilted towards the affected side. At roll tilt to the affected side, 9 of the 11 patients set the light bar in the same direction as their body tilt (undercorrection). At a tilt to the unaffected side 6 of the 11 patients made an undercorrection. For the group of patients the magnitude of undercorrection was larger at tilt to the affected side than to the unaffected side. The patients' ability to correctly align the light bar with the true horizontal gradually improved but was found normal in both upright and tilted positions in only three of the nine patients at the last follow-up. In four of the six patients who still demonstrated pathologic results, these were met only in tilted positions. No significant correlation was found between the intensity of spontaneous nystagmus or the degree of caloric side difference and the deviation in setting of the light bar in upright or tilted positions. The large asymmetric perceptual responses at tilt found at onset might be explained by the two-directional organisation of the utricle.
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| 3. |
- Johansson, Pia, et al.
(författare)
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The effect on opioid peptides in the rat brain, after chronic treatment with the anabolic androgenic steroid, nandrolone decanoate
- 2000
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Ingår i: Brain Research Bulletin. - 0361-9230 .- 1873-2747. ; 51:5, s. 413-418
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Tidskriftsartikel (refereegranskat)abstract
- In recent years, an increase in abuse of anabolic androgenic steroids (AAS) has been seen among individuals not directly connected to sports. Clinical evidence suggests that abuse of these steroids may result in profound changes in personality, expressed by depressive symptoms, irritability and increased aggression. It is still unknown whether these alterations are related to changes in any particular transmitter system or whether they are persistent or reversible. In this study we focused on AAS effect on the endogenous dynorphin and enkephalin system in the brain. Male rats were given intramuscular injections of the AAS nandrolone decanoate (15 mg/kg), once daily for 2 weeks. The levels of the opioid peptide immunoreactivities (ir) were assessed by radioimmunoassay in two groups immediately after the treatment and in two other groups after additional 3 weeks without any drug treatment (recovery period). The result indicates that chronic AAS treatment increased the activity in the dynorphin B- and Met-enkephalin-Arg6Phe7-ir in the hypothalamus, striatum and periaqueductal gray (PAG) compared to controls. In addition, the steroid induced an imbalance between the dynorphin and the enkephalin opioid system in the nucleus accumbens, hypothalamus and PAG. This imbalance remained after the recovery period. Since increased peptide activity was found in brain regions regulating emotions, dependence, defensive reactions and aggression, it was suggested that the actual endogenous opioid systems are involved in previously reported AAS-induced changes in these behaviours.
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| 4. |
- LaForge, K. Steven, et al.
(författare)
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“Binge” cocaine differentially alters preproenkephalin mRNA levels in guinea pig brain
- 2003
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Ingår i: Brain Research Bulletin. - 0361-9230 .- 1873-2747. ; 59:5, s. 353-357
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Tidskriftsartikel (refereegranskat)abstract
- Male Hartley guinea pigs were administered i.p. injections of cocaine or saline for 2 or 7 days in a "binge" paradigm. RNA was isolated from dissected brain regions and levels of preproenkephalin mRNA and total RNA were quantified by RNase protection assays. Following 2 days of "binge" cocaine administration, no significant alterations in preproenkephalin mRNA levels were detected in six brain regions. Following 7 days of cocaine administration, however, lower levels of preproenkephalin mRNA were observed in the nucleus accumbens and hypothalamus of cocaine-treated animals and higher levels in the frontal cortex and amygdala. These findings differed from previous studies in the rat, so an additional experiment was performed with animals treated at the 7 day time point. For increased statistical power, data from the two experiments were combined and examined by two-way ANOVAs; in this combined analysis, increases in preproenkephalin mRNA were observed in frontal cortex, amygdala, and hippocampus, decreases were found in the nucleus accumbens and hypothalamus, with no change in thalamus, caudate putamen, or cerebellum. These observed differences between guinea pigs and rats make this species an interesting model for neurobiological studies of cocaine-induced alterations in neuropeptide gene expression in the mammalian brain.
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| 5. |
- Lundh, Dan
(författare)
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A kinetic model on calcium residues and facilitation
- 1998
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Ingår i: Brain Research Bulletin. - : Elsevier. - 0361-9230 .- 1873-2747. ; 45:6, s. 589-597
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Tidskriftsartikel (refereegranskat)abstract
- The role of calcium as a regulator for neuronal function is very important. Calcium initiates many reactions that determine the behavior of the neuronal cell. In this article we use a kinetic model of the presynaptic synapsin I protein. This protein is responsible, via phosphorylation, for regulating the amount of transmitter vesicles available for release. This protein has been shown to inhibit the amount of vesicles ready for release in its dephosphorylated state, and releases its inhibitory binding due to phosphorylation. The phosphorylation of synapsin I depends on cyclic adenosine monophosphate and type II calcium/calmodulin protein kinase. Due to the duration of these two second messengers, we show that short-term facilitation does not have to depend on calcium residues. Furthermore, we show that calcium residues (in parts of μM range) promote increased facilitation due to the additional calcium reacting with the second messenger system.
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| 6. |
- Ploj, Karolina, et al.
(författare)
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Basal levels and alcohol-induced changes in nociceptin/orphanin FQ, dynorphin, and enkephalin levels in C57BL/6J mice
- 2000
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Ingår i: Brain Research Bulletin. - 0361-9230 .- 1873-2747. ; 53:2, s. 219-226
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Tidskriftsartikel (refereegranskat)abstract
- In order to investigate the involvement of the opioid and nociceptin/orphanin FQ (N/OFQ) system in alcohol drinking behaviour, N/OFQ and the opioid peptides dynorphin B (DYNB) and Met-enkephalin-Arg(6) Phe(7) (MEAP) were examined in the alcohol-preferring C57BL/6J mice. Basal peptide levels were compared in the brain and the pituitary gland with basal levels in the alcohol-avoiding DBA/2J mice. Furthermore, the effects of chronic alcohol self-administration on peptides were studied in the C57BL/6J mice. Compared to the DBA/2J mice, C57BL/6J mice had low immunoreactive (ir) levels of DYNB and MEAP in the nucleus accumbens, the hippocampus, and the substantia nigra, low ir-DYNB levels in the striatum and low ir-MEAP levels in the frontal cortex. Higher ir-DYNB levels in the pituitary gland and in the periaqueductal gray (PAG) and higher ir-N/OFQ levels in the frontal cortex and in the hippocampus were detected in C57BL/6J mice compared to the DBA/2J mice. After 4 weeks of voluntary alcohol consumption, only minor changes in steady-state peptide levels were identified. However, 5 days after the alcohol-drinking period, lower levels of all peptides were detected in the ventral tegmental area and ir-DYNB levels were also lower in the amygdala and in the substantia nigra. Twenty-one days after cessation of alcohol self-administration, the opioid peptides in alcohol-consuming C57BL/6J mice were lower in the PAG, the N/OFQ was lower in the frontal cortex and DYNB was higher in the amygdala and substantia nigra as compared to control C57BL/6J mice. This study demonstrates strain differences between C57BL/6J mice and DBA/2J mice that could contribute to divergent drug-taking behaviour, and it also demonstrates time- and structure-specific changes in neuropeptide levels after alcohol self-administration in the C57BL/6J mice.
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| 7. |
- Ploj, Karolina, et al.
(författare)
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Effects of melanocortin receptor ligands on ethanol intake and opioid peptide levels in alcohol-preferring AA rats
- 2002
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Ingår i: Brain Research Bulletin. - 0361-9230 .- 1873-2747. ; 59:2, s. 97-104
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Tidskriftsartikel (refereegranskat)abstract
- Melanocortin (MC) peptides are suggested to play a role in opiate dependence, where they antagonise the addictive properties of opiates. To further study the involvement of the MCs in drug dependence, we analysed the effects of the MC(4)-receptor antagonist HS014 (1 nmol/rat), and the non-selective MC-receptor agonist MTII (1 nmol/rat), using i.c.v. administration, on ethanol intake in alcohol-preferring AA rats. The rats had access to ethanol during 40 days, resulting in a mean ethanol intake of 6.6 g/kg/day, before treatment. One group received only artificial cerebrospinal fluid solution. MTII caused a reduction in ethanol intake and ethanol preference, whereas HS014 was without effect. No effect on water intake was observed. A decrease in food intake was detected after MTII, whereas HS014 induced an increase in food intake. Analysis of dynorphin B and Met-enkephalin-Arg(6)Phe(7) immunoreactive levels revealed that MTII and HS014 altered opioid peptide levels in several brain areas and the pituitary gland of the rats with an established ethanol intake. This is the first report showing that manipulation of the MC-receptor system changes ethanol intake in chronically ethanol-drinking AA rats. In addition, manipulation of the MC system modulates ethanol-induced changes in opioid peptide levels.
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| 8. |
- Tribukait, Arne, et al.
(författare)
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The subjective visual horizontal for different body tilts in the roll plane : characterization of normal subjects
- 1996
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Ingår i: Brain Research Bulletin. - 0361-9230 .- 1873-2747. ; 40:5-6, s. 375-383
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Tidskriftsartikel (refereegranskat)abstract
- In order to establish a method for estimation of the perceptual horizontal as a test of otolith function in diagnosis of atypical vertigo, in a first study we have standardized a test procedure and characterized a body of normal material consisting of 72 healthy subjects, 24 of them examined with tests followed by retests. The perceptual visual horizontal in darkness was estimated in the upright body position and at body tilts of 10, 20, and 30 degrees to the right and to the left by means of a narrow luminous bar. The deviation of the perceptual horizontal relative to the gravitational horizontal is expressed as a function of body tilt. In the upright body position, 95% had a perceptual horizontal within the range of +/- 2.5 degrees. In the tilted positions, there was a tendency to set the light bar tilted oppositely with respect to the body tilt. The results suggest that roll tilt to the right and to the left is sensed by two independent functional units. Furthermore, the results imply that some other factor might be of importance and that the perceptual horizontal in the upright position and tilt perception are complementary in reflecting vestibular function. Differences between individuals were great in comparison with intraindividual variability and the test-retest variability. The results are discussed against the background of the extensive literature.
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| 9. |
- Aylward, E H, et al.
(författare)
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Caudate volume as an outcome measure in clinical trials for Huntington's disease : a pilot study.
- 2003
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Ingår i: Brain Research Bulletin. - 0361-9230 .- 1873-2747. ; 62:2, s. 137-41
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Tidskriftsartikel (refereegranskat)abstract
- Previous research has demonstrated that longitudinal change in caudate volume could be observed over a period of 3 years in subjects with Huntington's disease (HD). The current pilot study was designed to determine whether measurement of caudate change on magnetic resonance imaging (MRI) is a feasible and valid outcome measure in an actual clinical trial situation. We measured caudate volumes on pre- and post-treatment MRI scans from 19 patients at two sites who were participating in CARE-HD (Co-enzyme Q10 and Remacemide: Evaluation in Huntington's Disease), a 30-month clinical trial of remacemide and co-enzyme Q(10) in symptomatic patients with HD. Results from this pilot study indicated that decrease in caudate volume was significant over time. Power analysis indicated that relatively small numbers of subjects would be needed in clinical trials using caudate volume as an outcome measure. Advantages and disadvantages of using MRI caudate volume as an outcome measure are presented. We recommend the adoption of quantitative neuroimaging of caudate volume as an outcome measure in future clinical trials for treatments of HD.
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| 10. |
- Binnewies, Julia, et al.
(författare)
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Lifestyle-related risk factors and their cumulative associations with hippocampal and total grey matter volume across the adult lifespan : a pooled analysis in the European Lifebrain consortium
- 2023
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Ingår i: Brain Research Bulletin. - : Elsevier. - 0361-9230 .- 1873-2747. ; 200
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Tidskriftsartikel (refereegranskat)abstract
- Background: Lifestyle-related risk factors, such as obesity, physical inactivity, short sleep, smoking and alcohol use, have been associated with low hippocampal and total grey matter volumes (GMV). However, these risk factors have mostly been assessed as separate factors, leaving it unknown if variance explained by these factors is overlapping or additive. We investigated associations of five lifestyle-related factors separately and cumulatively with hippocampal and total GMV, pooled across eight European cohorts.Methods: We included 3838 participants aged 18–90 years from eight cohorts of the European Lifebrain consortium. Using individual person data, we performed cross-sectional meta-analyses on associations of presence of lifestyle-related risk factors separately (overweight/obesity, physical inactivity, short sleep, smoking, high alcohol use) as well as a cumulative unhealthy lifestyle score (counting the number of present lifestyle-related risk factors) with FreeSurfer-derived hippocampal volume and total GMV. Lifestyle-related risk factors were defined according to public health guidelines.Results: High alcohol use was associated with lower hippocampal volume (r = −0.10, p = 0.021), and overweight/obesity with lower total GMV (r = −0.09, p = 0.001). Other lifestyle-related risk factors were not significantly associated with hippocampal volume or GMV. The cumulative unhealthy lifestyle score was negatively associated with total GMV (r = −0.08, p = 0.001), but not hippocampal volume (r = −0.01, p = 0.625).Conclusions: This large pooled study confirmed the negative association of some lifestyle-related risk factors with hippocampal volume and GMV, although with small effect sizes. Lifestyle factors should not be seen in isolation as there is evidence that having multiple unhealthy lifestyle factors is associated with a linear reduction in overall brain volume.
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