Memory-related effects of cholinergic receptor ligands in mice as measured by the elevated plus maze test.
Journal Title: Pharmacological Reports - Year 2011, Vol 63, Issue 6
Abstract
The purpose of our experiments was to examine the influence of cholinergic receptor ligands on memory-related behavior in mice using the elevated plus maze (EPM) test. The EPM test allows the exploration of different memory processes (acquisition and consolidation), depending on the time of drug treatment. The time necessary for mice to move from the opened arm to the enclosed arm (i.e., transfer latency, TL) was used as an index of memory. Our findings reveal that for both the processes of acquisition and consolidation, treatment with nicotine (0.035 or 0.175 mg/kg, free base, sc) shortened TL on the second day of the experiments (TL2), thus improving memory processes. Treatment with scopolamine (0.3 or 1.0 mg/kg, ip) significantly increased TL2 values, thus impairing cognitive processes. Moreover, we found that treatment with nicotine, at the non-effective doses used during testing, prevented scopolamine-induced memory impairment by inducing a decrease in TL2 values. Next, we evaluated the influence of bupropion (10 or 20 mg/kg, ip), a drug currently used for smoking cessation in humans, on memory-related behavior induced by treatment with nicotine and scopolamine. An acute injection of bupropion (10 or 20 mg/kg) prior to injection with either nicotine (0.035 mg/kg) or scopolamine (1.0 mg/kg) significantly prevented nicotine-induced memory improvement or scopolamine-induced memory impairment. Bupropion treatment can diminish the rewarding (dependence-producing) effects of nicotine and also the cognitive effects that are related to addiction. Our studies further indicate the great involvement of the cholinergic system in memory processes and the potential for the development of more effective pharmacotherapies for memory impairment-like human disorders in which the cholinergic pathways have been implicated.
Authors and Affiliations
Marta Kruk, Kinga Tendera, Grażyna Biała
Effect of metformin on selected parameters of hemostasis in fenofibrate-treated patients with impaired glucose tolerance.
Background: No previous study has assessed whether the addition of metformin potentiates fibrate action on hemostasis in prediabetic subjects. Methods: Our study included 41 fenofibrate-treated patients with impaired glu...
Autoinduction of the metabolism of phenothiazine neuroleptics in a primary culture of human hepatocytes.
BACKGROUND: The metabolism of phenothiazine neuroleptics (promazine, perazine) in a primary culture of human hepatocytes after pretreatment of cells with those neuroleptics was studied. METHODS: The hepatocytes were pret...
Acute exposure to caffeine decreases the anticonvulsant action of ethosuximide, but not that of clonazepam, phenobarbital and valproate against pentetrazole-induced seizures in mice.
This study examines the effect of acute administration of caffeine sodiumbenzoate (CAF) on the anticonvulsant action of four conventional antiepileptic drugs (AEDs: clonazepam - CZP, ethosuximide - ETS, phenobarbital - P...
Effect of risperidone on the fluoxetine-induced changes in extracellular dopamine, serotonin and noradrenaline in the rat frontal cortex.
Background: Several clinical reports have documented a beneficial effect of the addition of a low dose of risperidone to the ongoing treatment with antidepressants, in particular selective serotonin reuptake inhibitors,...
Allyl disulfide as donor and cyanide as acceptor of sulfane sulfur in the mouse tissues.
Cytoplasm of mammalian glial cells was reported to contain Gomori-positive cytoplasmic granulation (GPCG), whose biological role is unknown. The present study attempted to discover conditions facilitating GPCG formation...