The behavioural and electrophysiological effects of CRF in rat frontal cortex.

Corticotropin releasing factor (CRF) is a neuropeptide widely distributed in the brain. The role of CRF in the behavioural activity and modulation of anxiety states in several brain structures has been well documented, but its function in the cerebral cortex still remains unknown. The aim of our study was to investigate the effect of CRF injected bilaterally into rat frontal cortex on the locomotor and exploratory activity and anxiety of rats.

Cocaine decreases the expression of PSA-NCAM protein and attenuates long-term potentiation via glucocorticoid receptors in the rat dentate gyrus.

The present study investigated a potential role for glucocorticoid (GR) and mineralocorticoid (MR) receptors in the detrimental effects of single cocaine (COC) administration on both the number of polysialylated neural cell adhesion molecule (PSA-NCAM)-positive neurons and the induction of long-term potentiation (LTP) in the rat dentate gyrus (DG). The effects of COC (15 mg/kg i.p.

Effects of repetitive administration of tianeptine, zinc hydroaspartate and electroconvulsive shock on the reactivity of 5-HT(7) receptors in rat hippocampus.

The influence of repeated administration of tianeptine, an atypical antidepressant, which was administered twice daily (10 mg/kg) for 14 days and zinc hydroaspartate, a compound exhibiting antidepressant-like activity, which was administered twice daily (65 mg/kg) for 14 days, and the effects of electroconvulsive shocks (ECS) delivered once daily for 10 days, were investigated ex vivo in rat hippocampal slices. Slices were prepared 2 days after the last session of treatment of animals, and spontaneous epileptiform bursts were recorded extracellularly from the CA3 area. 5-HT(7) receptor-mediated increase in bursting frequency was induced by bath application of of 5-carboxamidotryptamine (5-CT; 0.

Repeated administration of citalopram and imipramine alters the responsiveness of rat hippocampal circuitry to the activation of 5-HT7 receptors.

The effects of a selective serotonin reuptake inhibitor, citalopram, and a tricyclic antidepressant drug, imipramine, administered repetitively for 14 days, were investigated ex vivo in rat hippocampal slices. Spontaneous epileptiform bursts were recorded from the CA3 area in nominally Mg(2+)-free incubation conditions. 5-carboxamidotryptamine (5-CT) dose-dependently increased bursting frequency in the presence of N-[2-[4-(2-methoxyphenyl)-1 piperazinyl]ethyl]-N-2-pyridinylcyclohexanecarboxamide (WAY 100635).

Chemically-induced long-term potentiation in rat motor cortex involves activation of extracellular signal-regulated kinase cascade.

The involvement of the extracellular signal-regulated kinase 1/2 (ERK1/2) cascade in long-lasting potentiation of synaptic transmission, induced by tetraethylammonium (TEA) or by elevated extracellular calcium concentration, was investigated in layer V horizontal connections within motor cortex in rat brain slices. Brief application of TEA (25 mM) resulted in a long-lasting potentiation of field potentials by 54+/-12%. A transient exposure of slices to elevated extracellular calcium (5 mM) induced long-lasting potentiation of responses reaching 30+/-8%.