Neuroscience letters
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Neuroscience letters · Nov 2006
Postischemic exercise decreases neurogenesis in the adult rat dentate gyrus.
Running exercise enhances neurogenesis in the normal adult and aged hippocampus. However, the effect of exercise on neurogenesis in the ischemic hippocampus is unclear. Here, we show that running exercise has different effects on ischemic and non-ischemic brain. ⋯ The numbers of BrdU-labeled cells were increased in response to ischemia, however, they were decreased 14 days after BrdU administration and running exercise accelerated the reduction in BrdU-labeled cells in ischemic rats. These findings suggest that running exercise has a negative effect on neurogenesis in the ischemic hippocampus. This may be important with respect to assessment of therapeutic approaches for functional recovery after stroke.
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Neuroscience letters · Nov 2006
Comparative StudyEffects of high dose of simvastatin on levels of dopamine and its reuptake in prefrontal cortex and striatum among SD rats.
Statins are increasingly being used for the treatment of a variety of conditions beyond their original indication for cholesterol lowering. We previously reported that simvastatin increased dopamine receptors in the rat prefrontal cortex [Q. Wang, W. ⋯ Dopamine (DA) reuptake was unchanged in both brain regions. These results suggest that chronic treatment with high dose of simvastatin may affect DA tissue level in prefrontal cortex and striatum without changing on DA reuptake. This may have important clinical implications in psychiatric and striatal dopaminergic disorders.
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Neuroscience letters · Nov 2006
Comparative StudySeverity level and injury track determine outcome following a penetrating ballistic-like brain injury in the rat.
Penetrating ballistic brain injury (PBBI) is a high-energy transfer wound causing direct damage to the cerebrum. Outcome is directly related to the ballistic's anatomical path and degree of energy transfer. In this study we evaluated differences in outcome induced by altering the 'projectile' paths and severity levels of a simulated bullet wound using a newly characterized rat model of PBBI. ⋯ A unilateral caudal injury was associated with the highest degree of mortality (up to 100%) and motor dysfunction (64-100% disability). Bilateral hemispheric injuries were also potentially fatal, while the best outcomes were associated with a unilateral frontal injury (no mortality and 14-39% motor disability). These data closely resemble clinical reports of ballistic wounds to the head and further validate the rat PBBI model with the ultimate intent to investigate novel therapeutic approaches for diagnosis and treatment of the neuropathological damage associated with PBBI.
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Neuroscience letters · Nov 2006
Effect of gabaergic, glutamatergic, antipsychotic and antidepressant drugs on pilocarpine-induced seizures and status epilepticus.
This work was designed to study the influence of drugs during seizures and status epilepticus (SE) induced by pilocarpine and mortality in adult rats. Fluoxetine (10 and 20 mg/kg), NMDA (N-methyl-D-aspartate, 10 and 20 mg/kg), amitriptyline (25 and 50 mg/kg), ketamine (0.5 and 1.0 mg/kg), gabapentin (100 and 150 mg/kg) and pimozide (10 and 20 mg/kg) were administered intraperitoneally, 30 min prior to pilocarpine (400mg/kg, s.c.). The animals were observed (24h) to determine: number of peripheral cholinergic signs, tremors, stereotyped movements, seizures, SE, latency to first seizure and number of deaths after pilocarpine treatment. ⋯ Smaller and higher doses of these drugs no protected and increased pilocarpine-induced seizures and/or mortality. Gabapentin and ketamine protected against seizures and reduced the latency to first seizure. Thus, these results suggest that caution should be taken in the selection of pharmacotherapy and dosages for patients with epilepsy because of the possibility of potentiating convulsive process toxicity.