Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Rotarod Performance Test”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 217 records · Page 12Linked to original sources

Cataleptic activity of the denatured venom of the social wasp Agelaia vicina (Hymenoptera, Vespidae) in Rattus norvegicus (Rodentia, Muridae).

Catalepsy is a state of immobility, commonly experienced by patients with chronic use of many antiparkisonism and neuroleptic drugs. Recently, catatonia has been considered as an evolutionary-based fear response. The cataleptogenic effects of the low molecular weight compounds from the venom of the social wasp A. vicina (AdAv) were reported in rodents. Intracerebroventricular injections of AdAv in highest dose reduced the locomotor activity of Wistar rats in the open field and induced ataxia and catalepsy within 10 min. This effect could be observed up to 30 min after injections. Lower doses of denatured venom injected in brain ventricles also reduced the locomotor activity of the rats but did not induce catalepsy. The cataleptic effects of the intracerebrally administered AdAv were antagonized by the peripheral (intraperitoneal) pretreatment with theophylline and ketamine. Moreover, the central effects of the AdAv were compared to those elicited by the neuroleptic drug haloperidol (intraperitoneally administered), whose cataleptic effects were also antagonized by theophylline and ketamine. However, the association of haloperidol and denatured venom was reverted by theophylline but not by ketamine. These findings suggest that A. vicina venom may affect neural substrates involved with catalepsy in the central nervous system.

Analysis of Variance↗

Combined therapy affects outcomes differentially after mild traumatic brain injury and secondary forebrain ischemia in rats.

Muscarinic and NMDA receptors contribute to post-traumatic hypersensitivity to secondary ischemia. However, the effect of these receptor antagonists on behavior and CA1 neuronal death after traumatic brain injury (TBI) with acute (1 h after TBI) forebrain ischemia has not been systematically assessed. We examined cognitive and motor dysfunction and the relationship of behavior deficits to neuronal death in this model using muscarinic and NMDA antagonists. Three behavioral groups (n=10/group) of Wistar rats were subjected to mild TBI and 6 min of forebrain ischemia imposed 1 h after TBI with 45 days survival. Motor and spatial memory performance were assessed using the rotarod task and Morris water maze. Seven additional groups (n=6/group) were evaluated only for CA1 death after 7 days survival following sham, individual or combined injury with and without drug treatments. Rats were given 0.3 mg/kg MK-801 (M) and 1.0 mg/kg scopolamine (S) alone or combined (M-S) before or 45 min after TBI. Rotarod performance was tested at days 1-5 and maze performance on days 11-15 and 40-44 after M-S treatment. The 7-day studies showed M-S treatment (p<0.01) reduced CA1 neuronal death better than either S or M alone. Behavioral groups had inadvertent post-ischemic hypothermia that decreased CA1 death and likely influenced behavioral morbidity. M-S given before TBI (p<0.01) decreased memory deficits on day 15, while M-S treatment given after TBI was ineffective. Unexpectedly, M-S treatment before or after TBI produced transient motor deficits (p<0. 01). Memory improvement occurred independent of CA1 death.

Animals↗

Neuropharmacological activity of Nigella sativa L. extracts.

Pharmacological studies have been conducted on the aqueous and methanol extracts of defatted Nigella sativa L. seeds to evaluate their effects on the central nervous system (CNS) and on analgesic activity. The observations suggest that the two extracts of Nigella sativa possesses a potent CNS and analgesic activity (depressant action especially in the case of the methanolic extract).

Animals↗

Differential role for CBP and p300 CREB-binding domain in motor skill learning.

Cyclic adenosine monophosphate response element binding protein (CREB) binding protein (CBP) and E1A binding protein (p300) are highly homologous transcriptional coactivators with histone acetyltransferase activity. Although CBP and p300 have unique functions in vivo during embryogenesis and hematopoiesis, their functions within the nervous system remain poorly understood. The authors demonstrate that these coactivators have differential roles in motor skill learning. Mice with a mutation in the CREB-binding (KIX) domain of CBP exhibited motor learning deficits. However, mice with the analogous mutation in the KIX domain of p300 showed normal motor learning. Further, CREB knock-out mice exhibited a motor learning deficit similar to that of CBP-KIX mutant mice. These results suggest that the CREB-CBP interaction is more limiting or critical than the CREB-p300 interaction for motor skill learning. Thus, CBP and p300 are genetically distinct at the behavioral level.

Analysis of Variance↗

Acute functional tolerance to ethanol mediated by protein kinase Cepsilon.

A low level of response to ethanol is associated with increased risk of alcoholism. A major determinant of the level of response is the capacity to develop acute functional tolerance (AFT) to ethanol during a single drinking session. Mice lacking protein kinase C epsilon (PKCepsilon) show increased signs of ethanol intoxication and reduced ethanol self-administration. Here, we report that AFT to the motor-impairing effects of ethanol is reduced in PKCepsilon (-/-) mice when compared with wild-type littermates. In wild-type mice, in vivo ethanol exposure produced AFT that was accompanied by increased phosphorylation of PKCepsilon and resistance of GABA(A) receptors to ethanol. In contrast, in PKCepsilon (-/-) mice, GABA(A) receptor sensitivity to ethanol was unaltered by acute in vivo ethanol exposure. Both PKCepsilon (-/-) and PKCepsilon (+/+) mice developed robust chronic tolerance to ethanol, but the presence of chronic tolerance did not change ethanol preference drinking. These findings suggest that ethanol activates a PKCepsilon signaling pathway that contributes to GABA(A) receptor resistance to ethanol and to AFT. AFT can be genetically dissociated from chronic tolerance, which is not regulated by PKCepsilon and does not alter PKCepsilon modulation of ethanol preference.

Alcohol Drinking↗

Connexin30-deficient mice show increased emotionality and decreased rearing activity in the open-field along with neurochemical changes.

Gap-junction channels in the brain, formed by connexin (Cx) proteins with a distinct regional/cell-type distribution, allow intercellular electrical and metabolic communication. In astrocytes, mainly the connexins 43, 26 and 30 are expressed. In addition, connexin30 is expressed in ependymal and leptomeningeal cells, as well as in skin and cochlea. The functional implications of the astrocytic gap-junctional network are not well understood and evidence regarding their behavioural relevance is lacking. Thus, we have tested groups of Cx30-/-, Cx30+/-, and Cx30+/+ mice in the open-field, an object exploration task, in the graded anxiety test and on the rotarod. The Cx30-/- mice showed reduced exploratory activity in terms of rearings but not locomotion in the open-field and object exploration task. Furthermore, Cx30-/- mice exhibited anxiogenic behaviour as shown by higher open-field centre avoidance and corner preference. Graded anxiety test and rotarod performance was similar across groups. The Cx30-/- mice had elevated choline levels in the ventral striatum, possibly related to their aberrant behavioural phenotypes. The Cx30+/- mice had lower dopamine and metabolite levels in the amygdala and ventral striatum and lower hippocampal 5-hydroxyindole acid (5-HIAA) concentrations relative to Cx30+/+ mice. Furthermore, the Cx30+/- mice had lower acetylcholine concentrations in the ventral striatum and higher choline levels in the neostriatum, relative to Cx30+/+ mice. Our data suggest that the elimination of connexin30 can alter the reactivity to novel environments, pointing to the importance of gap-junctional signalling in behavioural processes.

Acetylcholine↗

Mice with astrocyte-directed inactivation of connexin43 exhibit increased exploratory behaviour, impaired motor capacities, and changes in brain acetylcholine levels.

Gap junctions mediate communication between many cell types in the brain. Gap junction channels are composed of membrane-spanning connexin (Cx) proteins, allowing the cell-to-cell passage of small ions and metabolites. Cx43 is the main constituent of the brain-spanning astrocytic gap junctional network, controlling activity-related changes in ion and glutamate concentrations as well as metabolic processes. In astrocytes, deletion of Cx43-coding DNA led to attenuated gap junctional coupling and impaired propagation of calcium waves, known to influence neuronal activity. Investigation of the role of Cx43 in behaviour has been impossible so far, due to postnatal lethality of its general deletion. Recently, we have shown that deletion of Cx30, which is also expressed by astrocytes, affects exploration, emotionality, and neurochemistry in the mouse. In the present study, we investigated the effects of the astrocyte-directed inactivation of Cx43 on mouse behaviour and brain neurochemistry. Deletion of Cx43 in astrocytes increased exploratory activity without influencing habituation. In the open field, but not in the elevated plus-maze, an anxiolytic-like effect was observed. Rotarod performance was initially impaired, but reached control level after further training. In the water maze, Cx43 deficient mice showed a steeper learning course, although final performance was similar between groups. Cx43 inactivation in astrocytes increased acetylcholine content in the frontal cortex of water maze-trained animals. Results are discussed in terms of altered communication between astrocytes and neurons, possible compensation processes, and differential effects of Cx30- and astrocyte-specific Cx43 deletion.

3,4-Dihydroxyphenylacetic Acid↗

Absence of behavioral abnormalities and neurodegeneration in vivo despite widespread neuronal huntingtin inclusions.

We have serendipitously established a mouse that expresses an N-terminal human huntingtin (htt) fragment with an expanded polyglutamine repeat (approximately 120) under the control of the endogenous human promoter (shortstop). Frequent and widespread htt inclusions occur early in shortstop mice. Despite these inclusions, shortstop mice display no clinical evidence of neuronal dysfunction and no neuronal degeneration as determined by brain weight, striatal volume, and striatal neuronal count. These results indicate that htt inclusions are not pathogenic in vivo. In contrast, the full-length yeast artificial chromosome (YAC) 128 model with the identical polyglutamine length and same level of transgenic protein expression as the shortstop demonstrates significant neuronal dysfunction and loss. In contrast to the YAC128 mouse, which demonstrates enhanced susceptibility to excitotoxic death, the shortstop mouse is protected from excitotoxicity, providing in vivo evidence suggesting that neurodegeneration in Huntington disease is mediated by excitotoxic mechanisms.

Analysis of Variance↗

Magnesium gluconate offers no more protection than magnesium sulphate following diffuse traumatic brain injury in rats.

OBJECTIVE: Previous studies have demonstrated that magnesium salts, including the sulphate and chloride forms, are neuroprotective following traumatic brain injury (TBI). Recently, studies in cardiac ischaemia/reperfusion injury have demonstrated that the gluconate salt of magnesium may provide superior protection against oxidative damage and postischaemic dysfunction than MgSO(4). We have therefore compared the efficacy of both MgSO(4) and magnesium gluconate (MgGl(2)) on outcome following diffuse TBI in rats. METHODS: Adult male Sprague-Dawley rats were injured using the 2-metre impact acceleration model of diffuse TBI. At 30 min after injury, animals were administered with either 250 micromoles/kg i.v. MgSO(4), MgGl(2), or equal volume saline vehicle. Thereafter, animals were assessed for motor and cognitive outcome using the rotarod and Barnes maze, respectively, or their brains removed at 3 days after TBI and used for histological examination. RESULTS: Treatment with either magnesium salt significantly improved functional outcome as compared to vehicle treated controls. Similarly, treatment with either magnesium salt attenuated the degree of histological dark cell change at 3 days after TBI relative to the vehicle treated animals. There were no significant differences between the magnesium treated groups. CONCLUSIONS: We conclude that MgSO(4) and MgGl(2) are equally neuroprotective following TBI. Our results suggest that MgGl(2) may only be more effective in conditions that produce ischaemia, where high concentrations of reactive oxygen species are generated.

Animals↗

Morphological alterations of central nervous system (CNS) myelin in vanadium (V)-exposed adult rats.

In the present work we show morphological data of the in vivo susceptibility of CNS myelin to sodium metavanadate [V(+5)] in adult rats. The possible role of vanadium in behavioral alterations and in brain lipid peroxidation was also investigated. Animals were injected intraperitoneally (i.p.) with 3 mg/kg body weight (bw) of sodium metavanadate [1.25 V/kg bw/day] for 5 consecutive days. Open field and rotarod tests were performed the day after the last dose had been administered and then animals were sacrificed by different methods for histological and lipid peroxidation studies. The present results show that intraperitoneal administration of V(+5) to adult rats resulted in changes in locomotor activity, specific myelin stainings and lipid peroxidation in some brain areas. They support the notion that CNS myelin could be a preferential target of V(+5)-mediated lipid peroxidation in adult rats. The mechanisms underlying this action could affect the myelin sheath leading to behavioral perturbations.

Animals↗

Sodium butyrate ameliorates phenotypic expression in a transgenic mouse model of spinal and bulbar muscular atrophy.

Spinal and bulbar muscular atrophy (SBMA) is an inherited motor neuron disease caused by the expansion of a polyglutamine (polyQ) tract within the androgen receptor. Unifying mechanisms have been implicated in the pathogenesis of polyQ-dependent neurodegenerative diseases including SBMA, Huntington disease and spinocerebellar ataxias. It has been suggested that mutant protein containing polyQ inhibits histone acetyltransferase activity, resulting in transcriptional dysfunction and subsequent neuronal dysfunction. Histone deacetylase (HDAC) inhibitors alleviate neurological phenotypes in fly and mouse models of polyQ disease, although the therapeutic effect is limited by the toxicity of these compounds. We studied the therapeutic effects of sodium butyrate (SB), an HDAC inhibitor, in a transgenic mouse model of SBMA. Oral administration of SB ameliorated neurological phenotypes as well as increased acetylation of nuclear histone in neural tissues. These therapeutic effects, however, were seen only within a narrow range of SB dosage. Our results indicate that SB is a possible therapeutic agent for SBMA and other polyQ diseases, although an appropriate dose should be determined for clinical application.

Acetylation↗

Characterization of Ighmbp2 in motor neurons and implications for the pathomechanism in a mouse model of human spinal muscular atrophy with respiratory distress type 1 (SMARD1).

Spinal muscular atrophy with respiratory distress type 1 (SMARD1) is caused by recessive mutations of the IGHMBP2 gene. The role of IGHMBP2 (immunoglobulin mu-binding protein 2) in the pathomechanism of motor neuron disease is unknown. We have generated antibodies against Ighmbp2 and showed that low levels of Ighmbp2 immunoreactivity are present in the nucleus of spinal motor neurons and high levels in cell bodies, axons and growth cones. Ighmbp2 protein levels are strongly reduced in neuromuscular degeneration (nmd) mice, the mouse model of SMARD1. Mutant mice show severe motor neuron degeneration before first clinical symptoms become apparent. The loss of motor neuron cell bodies in lumbar spinal cord is followed by axonal degeneration in corresponding nerves such as the femoral quadriceps and sciatic nerve and loss of axon terminals at motor endplates. Motor neuron degeneration and clinical symptoms then slowly progress until the mice die at the age of 3-4 months. In addition, myopathic changes seem to contribute to muscle weakness and especially to respiratory failure, which is characteristic of the disorder in humans. Cultured motor neurons from embryonic nmd mice did not show any abnormality with respect to survival, axonal growth or growth cone size, thus differing from motor neurons derived from, e.g. Smn (survival motor neuron) deficient mice, the model of spinal muscular atrophy (SMA). Our data suggest that the pathomechanism in SMARD1 is clearly distinct from other motor neuron diseases such as classic SMA.

Action Potentials↗

Contribution of nuclear and extranuclear polyQ to neurological phenotypes in mouse models of Huntington's disease.

In postmortem Huntington's disease brains, mutant htt is present in both nuclear and cytoplasmic compartments. To dissect the impact of nuclear and extranuclear mutant htt on the initiation and progression of disease, we generated a series of transgenic mouse lines in which nuclear localization or nuclear export signal sequences have been placed N-terminal to the htt exon 1 protein carrying 144 glutamines. Our data indicate that the exon 1 mutant protein is present in the nucleus as part of an oligomeric or aggregation complex. Increasing the concentration of the mutant transprotein in the nucleus is sufficient for and dramatically accelerates the onset and progression of behavioral phenotypes. Furthermore, nuclear exon 1 mutant protein is sufficient to induce cytoplasmic neurodegeneration and transcriptional dysregulation. However, our data suggest that cytoplasmic mutant exon 1 htt, if present, contributes to disease progression.

Animals↗

Proteasome impairment does not contribute to pathogenesis in R6/2 Huntington's disease mice: exclusion of proteasome activator REGgamma as a therapeutic target.

Huntington's disease (HD) is one of a group of neurodegenerative disorders caused by the pathological expansion of a glutamine tract. A hallmark of these so-called polyglutamine diseases is the presence of ubiquitylated inclusion bodies, which sequester various components of the 19S and 20S proteasomes. In addition, the ubiquitin-proteasome system (UPS) has been shown to be severely impaired in vitro in cells overexpressing mutant huntingtin. Thus, because of its fundamental housekeeping function, impairment of the UPS in neurons could contribute to neurotoxicity. We have recently proposed that the proteasome activator REGgamma could contribute to UPS impairment in polyglutamine diseases by suppressing the proteasomal catalytic sites responsible for cleaving Gln-Gln bonds. Capping of proteasomes with REGgamma could therefore contribute to a potential 'clogging' of the proteasome by pathogenic polyglutamines. We show here that genetic reduction of REGgamma has no effect on the well-defined neurological phenotype of R6/2 HD mice and does not affect inclusion body formation in the R6/2 brain. Surprisingly, we observe increased proteasomal 'chymotrypsin-like' activity in 13-week-old R6/2 brains relative to non-R6/2, irrespective of REGgamma levels. However, assays of 26S proteasome activity in mouse brain extracts reveal no difference in proteolytic activity regardless of R6/2 or REGgamma genotype. These findings suggest that REGgamma is not a viable therapeutic target in polyglutamine disease and that overall proteasome function is not impaired by trapped mutant polyglutamine in R6/2 mice.

Analysis of Variance↗

Intracerebral adeno-associated virus-mediated gene transfer in rapidly progressive forms of metachromatic leukodystrophy.

Metachromatic leukodystrophy (MLD) is a neurodegenerative lysosomal disease caused by a defect of the enzyme arylsulfatase A (ARSA) that disrupts the degradation of sulfatides (Sulf) in neurons and glial cells. Therapy for MLD requires active production of ARSA in the brain to prevent demyelination and neuronal damage, and efficient delivery of ARSA to act faster than disease progression, particularly in the rapidly progressive late infantile form. We used an adeno-associated virus serotype 5 (AAV5) vector to express the human ARSA gene in the brain of MLD mouse model. We achieved rapid, extensive and long-lasting expression of the recombinant ARSA in the brain, cerebellum and brainstem from at least 3 to 15 months post-injection. Analysis of the vector genome and ARSA distribution gave evidence for in vivo cross-correction of many untransduced neurons and astrocytes. ARSA delivery rapidly reversed Sulf storage and prevented neuropathological abnormalities and neuromotor impairment. We believe that AAV5-mediated brain delivery of ARSA is a potentially efficacious therapeutic strategy for MLD patients, especially for those with rapidly progressive form of the disease.

Adenoviridae↗

Progressive loss of motor neuron function in wasted mice: effects of a spontaneous null mutation in the gene for the eEF1 A2 translation factor.

Wasted (wst) is a spontaneous autosomal recessive mutation in which the gene encoding translation factor eEF1A2 is deleted. Homozygous mice show tremors and disturbances of gait shortly after weaning, followed by motor neuron degeneration, paralysis, and death by about 28 days. We have now conducted a more detailed analysis of neuromuscular pathology in these animals. Reactive gliosis was observed at 19 days postnatal in wst/wst cervical spinal cord, showing a rostrocaudal gradient. This was followed a few days later by motor neuron vacuolation and neurofilament accumulation, again with a rostrocaudal progression. Thoracic/abdominal muscles from wst/wst mice aged 17 days showed evidence of progressive denervation of motor endplates, including weak synaptic transmission and retraction of motor nerve terminals. Similar abnormalities appeared in distal, lumbrical muscles from about 25 days of age. We conclude that spontaneous failure of eEF1A2 expression in the wasted mutant first triggers gliosis in spinal cord and retraction of motor nerve terminals in muscle, and then motor neuron pathology and death. The early initiation and rapid progression of motor unit degeneration in wst/wst mice suggest that they should be considered an important and accessible model of early-onset motor neuron degeneration in humans.

Animals↗

Protein synthesis inhibition blocks consolidation of an acrobatic motor skill.

To investigate whether motor skill learning depends on de novo protein synthesis, adult rats were trained in an acrobatic locomotor task (accelerating rotarod) for 7 d. Animals were systemically injected with cycloheximide (CHX, 0.5 mg/kg, i.p.) 1 h before sessions 1 and 2 or sessions 2 and 3. Control rats received vehicle injections before sessions 1, 2, and 3. Although CHX did not affect improvement of performance within session 1, between-session improvement was impaired. In overtrained animals, comparable injections of CHX had no effect on rotarod performance. These findings suggest that consolidation of motor skills requires protein synthesis.

Analysis of Variance↗

Dissociation between short-term increased graft survival and long-term functional improvements in Parkinsonian rats overexpressing glial cell line-derived neurotrophic factor.

The present study was designed to analyse whether continuous overexpression of glial cell line-derived neurotrophic factor (GDNF) in the striatum by a recombinant lentiviral vector can provide improved cell survival and additional long-term functional benefits after transplantation of fetal ventral mesencephalic cells in Parkinsonian rats. A four-site intrastriatal 6-hydroxydopamine lesion resulted in an 80-90% depletion of nigral dopamine cells and striatal fiber innervation, leading to stable motor impairments. Histological analysis performed at 4 weeks after grafting into the GDNF-overexpressing striatum revealed a twofold increase in the number of surviving tyrosine hydroxylase (TH)-positive cells, as compared with grafts placed in control (green fluorescent protein-overexpressing) animals. However, in animals that were allowed to survive for 6 months, the numbers of surviving TH-positive cells in the grafts were equal in both groups, suggesting that the cells initially protected at 4 weeks failed to survive despite the continued presence of GDNF. Although cell survival was similar in both grafted groups, the TH-positive fiber innervation density was lower in the GDNF-treated grafted animals (30% of normal) compared with animals with control grafts (55% of normal). The vesicular monoamine transporter-2-positive fiber density in the striatum, by contrast, was equal in both groups, suggesting that long-term GDNF overexpression induced a selective down-regulation of TH in the grafted dopamine neurons. Behavioral analysis in the long-term grafted animals showed that the control grafted animals improved their performance in spontaneous motor behaviors to approximately 50% of normal, whereas the GDNF treatment did not provide any additional recovery.

Adrenergic Agents↗