These results demonstrate that electrical stimulation of the accumbens shell or core has a bidirectional effect on LTP induction at the dentate gyrus. (c) 2008 IBRO. Published by Elsevier Ltd. All rights reserved.”
“Ultrafine or fine titanium dioxide (TiO2) particles are widely used in the production of white pigments, for sunscreens, and in cleanup techniques. However, currently knowledge is deficient concerning cellular responses to these particles. The study evaluated and compared the biological activity of ultrafine and fine TiO2 particles in RAW 264.7 macrophages according to an oxidative stress paradigm. In vitro exposure of macrophages to ultrafine
or fine TiO2 in
the range of 0.5-200 mu g/ml did not significantly alter cell viability. However, ultrafine TiO2 buy Bucladesine enhanced intracellular generation of reactive oxygen species (ROS) to a greater extent than fine TiO2 at each exposure concentration. Ultrafine TiO2 induced ERK1/2 activation in a concentration-dependent manner, while the fine TiO2-induced changes were minimal. Phosphorylation of ERK1/2 occurred following 10 min exposure to higher concentrations of ultrafine TiO2 (>= 25 g/ml). Similarly, ultrafine TiO2 exposure significantly enhanced selleck products tumor necrosis factor (TNF)-alpha and macrophage inflammatory protein (MIP)-2 secretion in a concentration-dependent manner, and
its potency was higher than fine TiO2. These findings suggest that when exposure concentration is based upon equivalent mass, ultrafine TiO2 exerts greater biological activity as measured by ROS generation, ERK 1/2 activation, and proinflammatory mediator secretion in RAW 264.7 macrophages than fine TiO2.”
“Reinstatement of extinguished drug-seeking has been utilized in the study of the neural substrates of relapse to drugs of abuse, particularly cocaine. However, limited studies have examined the circuitry that drives the reinstatement of heroin-seeking behavior in the presence of conditioned cues, or by heroin itself. In order to test the hypothesis that the circuitry underlying reinstatement SPTBN5 in heroin-experienced animals would show overlapping, yet distinct differences from coca! ne-experienced animals, we used transient inhibition of several cortical, striatal, and limbic brain regions during reinstatement of heroin-seeking produced by heroin-paired cues, or by a single priming dose of heroin. Rats lever pressed for i.v. heroin discretely paired with a conditioned stimulus (CS) during daily 3-h sessions for a period of 2 weeks, followed by daily extinction of lever responding. Subsequent reinstatement of heroin-seeking was measured as lever responding in the absence of heroin reinforcement.