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Neuroplastic Change (neuroplastic + change)
Selected AbstractsNeuroplastic Changes in the Brain: A Case of Two Successive Adaptive Changes Within the Motor CortexJOURNAL OF NEUROIMAGING, Issue 3 2010Eytan Raz MD ABSTRACT We describe a case of neuroplasticity associated with both arteriovenous malformation (AVM) and stroke, which occurred in two successive events in the same patient. Functional magnetic resonance imaging (fMRI) during right-hand movement in a young man with a left rolandic AVM detected activation of a region corresponding to the left premotor cortex. The AVM was embolized. A few hours after the last embolization session, the patient sustained an ischemic complication in the left subcortical white matter. A second fMRI detected a lower degree of left premotor cortex activation and strong activation of the contralesional right primary motor cortex and bilateral supplementary motor areas. One month later, in association with clinical recovery, the fMRI activation returned to that observed in the first fMRI, ie, selective activation of the ipsilesional left premotor cortex. This is, to our knowledge, the first description of two distinct functional cortical changes determined by an AVM and a stroke within the motor network. [source] Neuropeptide S Receptor Gene Expression in Alcohol Withdrawal and Protracted Abstinence in Postdependent RatsALCOHOLISM, Issue 1 2010Barbara Ruggeri Background:, Alcoholism is a chronic disease characterized by frequent intoxications followed by withdrawal episodes and relapse to alcohol use. Neuroplastic changes associated with these intoxication and withdrawal cycles are thought to play a key role in disease progression. Recently, it has been shown that neuropeptide S (NPS), a newly deorphanized neuropeptide receptor system, facilitates relapse to alcohol seeking in laboratory animals. Given that a history of ethanol intoxication may increase vulnerability to alcohol addiction, we sought to determine whether NPS receptor (NPSR) gene expression is altered during withdrawal. Methods:, Rats were subjected to 1 week of intoxication by oral alcohol administration. NPSR gene expression was analyzed by in situ hybridization in rats 12 hours and 7 days after the last alcohol administration. To investigate the functional significance of NPSR system adaptation following protracted withdrawal 7 days after intoxication, we tested the anxiolytic-like properties of NPS in nondependent and postdependent rats using the shock probe defensive burying test (DB). Results:, At both time points, increased NPSR gene expression was observed in several brain areas, including the endopiriform nucleus, the motor cortex, and the medial amygdaloid nucleus. Moderate increases in gene expression were also found in the lateral hypothalamus, paraventricular nucleus, basolateral and central amygdala. Differences from control animals were more pronounced after 7 days of abstinence. The upregulation of the NPSR system at this time point was confirmed by functional data indicating that intracerebroventricular (ICV) NPS administration (0.0, 0.3, and 0.1 nmol/rat) elicits more pronounced anxiolytic effects in postdependent animals than in controls subjected to the electric shock probe DB test. Conclusions:, Neuropeptide S receptor mRNA expression is increased in different brain areas of postdependent rats; as shown in the DB test, this expression change is functionally relevant. [source] N-cadherin is regulated by gonadal steroids in adult sexually dimorphic spinal motoneuronsDEVELOPMENTAL NEUROBIOLOGY, Issue 4 2001Douglas A. Monks Abstract Gonadal steroids influence the morphology and function of neurons in the adult spinal cord through cellular and molecular mechanisms that are largely unknown. The cadherins are cell adhesion molecules that participate in the formation and organization of the CNS during embryonic development, and recent evidence suggests that the cadherins continue to regulate neural structure and function in adulthood. Using degenerate oligonucleotides coding conserved regions of the catenin-binding domain of classical cadherins in a RT-PCR cloning strategy, we identified several cadherin subtypes, the most frequently cloned being N-, E-, and R-cadherin, suggesting that these are the major classical cadherin subtypes present in the adult male rat lumbosacral spinal cord. We then examined cadherin expression levels of these cadherin subtypes under steroid conditions known to induce plastic changes in spinal motoneurons. Semiquantitative PCR revealed that mRNA levels of N-cadherin, but not E-cadherin or R-cadherin, are elevated in castrated rats treated with testosterone, 17,-estradiol, or dihydrotestosterone relative to castrate rats not treated with steroids. Immunolocalization of N-cadherin revealed that steroid treatment increased N-cadherin expression levels in functionally related neural populations whose morphology and function are regulated by steroids. These results suggest a role for N-cadherin in steroid-induced neuroplastic change in the adult lumbar spinal cord. © 2001 John Wiley & Sons, Inc. J Neurobiol 47: 255,264, 2001 [source] Developmental and activity-dependent genomic occupancy profiles of CREB in monkey area V1GENES, BRAIN AND BEHAVIOR, Issue 2 2009J. Lalonde The mammalian neocortex displays significant plastic rearrangement in response to altered sensory input, especially during early postnatal development. It is believed that cyclic AMP-response element-binding (CREB) plays an important role in orchestrating the molecular events that guide neuroplastic change, although the details of its genomic targets during normal postnatal development or in response to sensory deprivation remain unknown. Here, we performed CREB chromatin immunoprecipitation (ChIP) from monkey area V1 tissue and hybridized enriched DNA fragments to promoter microarrays (ChIP chip analysis). Our goal was to determine and categorize the CREB regulon in monkey area V1 at two distinct developmental stages (peak of critical period vs. adulthood) and after 5 days of monocular enucleation (ME) at both ages. Classification of enriched candidates showed that the majority of isolated promoter loci (n = 795) were common to all four conditions. A particularly interesting group of candidates (n = 192) was specific to samples derived from enucleated infant area V1. Gene ontology analysis of CREB targets during early postnatal development showed a subgroup of genes implicated in cytoskeleton-based structural modification. Analysis of messenger RNA expression (quantitative real-time,polymerase chain reaction) of candidate genes showed striking differences in expression profiles between infant and adult area V1 after ME. Our study represents the first extensive genomic analysis of CREB DNA occupancy in monkey neocortex and provides new insight into the multifaceted transcriptional role of CREB in guiding neuroplastic change. [source] Substance induced plasticity in noradrenergic innervation of the paraventricular hypothalamic nucleusEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2003Arthur S. P. Jansen Abstract Single administration of the cytokine interleukin-1, (IL-1), or the psychostimulant amphetamine, enhanced adrenocorticotropin hormone and corticosterone responses to a stress challenge weeks later. This long-lasting hypothalamic-pituitary-adrenal (HPA)-sensitization is paralleled by an increase in electrically evoked release of noradrenaline in the paraventricular hypothalamic nucleus (PVN). We hypothesized that these functional changes may be associated with morphological plasticity of noradrenergic projections to the PVN, a parameter that shows high reproducibility. Specific alterations in relative (nor)adrenergic innervation density were studied by using dopamine-,-hydroxylase (DBH) as a marker. An image analysis system was used to detect changes in the relative DBH innervation density of the PVN. Groups of adult male rats were given IL-1 (10 µg/kg i.p.), amphetamine (5 mg/kg i.p.), or saline. Three weeks later, IL-1 and amphetamine primed rats showed enhanced adrenocorticotropin hormone and corticosterone responses to an amphetamine challenge. In another set of experiments, the relative DBH innervation density was measured in different PVN subnuclei at four rostro-caudal levels. Single administration of either IL-1 or amphetamine causes three weeks later a selective decrease in relative DBH innervation density in those subnuclei of the PVN that contain high numbers of corticotrophin-releasing hormone (CRH) producing neurons: the dorsal parvocellular and medial parvocellular PVN. We conclude that (1) long-lasting sensitization induced by single exposure to IL-1 and amphetamine induces specific pattern of neuroplastic changes in (nor)adrenergic innervation in the PVN and (2) reduction of relative DBH innervation density in CRH-rich areas is associated with paradoxical increase of electrically evoked release of (nor)adrenaline. [source] | |||||||||||||