g.) for 14 days with either water or alcohol. In the following 5 days rats were injected (s.c.) with vehicle, nicotine, or WIN 55,212-2. Finally, a cannula was surgically implanted into the NAc shell and alcohol-induced extracellular
dopamine release was monitored in freely moving rats. Alcohol (1 g/kg; i.g.) only increased the release of dopamine when animals were previously treated with water. This DA increase was markedly inhibited by (subchronic) treatment (5 days) with nicotine or WIN 55-212-2 Evofosfamide solubility dmso as well as by previous (chronic) exposure to alcohol (14 days). These data demonstrate that pre-treatment with nicotine and the cannabinoid agonist WIN 55,212-2 is able to change the sensitivity of the NAc shell in response to a moderate dose of alcohol. Therefore, cannabinoid and nicotine
exposure may have important implications on the rewarding effects of alcohol, because these drugs lead to long-lasting changes in accumbal dopamine transmission. (c) 2007 Elsevier Ireland PLX4032 Ltd. All rights reserved.”
“The aim of the present study was to investigate whether direct activation of protein kinase C (PKC) in the spinal cord could change brain activation using a functional magnetic resonance imaging (fMRI) analysis in mice that lack the PKC gamma gene. The activation of spinal PKC by intrathecal (i.t.) injection with phorbol 12,13-dibutyrate (PDBu), a specific PKC activator, caused a time-dependent decrease in paw-withdrawal latency to the heat thermal stimulus. In contrast, i.t. injection of PDBu failed to cause thermal hyperalgesia in mice which lacked the PKC gamma gene. We found that the i.t. injection with PDBu R406 caused a remarkable increase in the activity of several brain regions in wild-type mice compared with vehicle injection. In the somatosensory cortex and lateral and medial thalamus, i.t. injection of PDBu produced a dramatic and time-dependent increase in signal intensity at 1-6 h after i.t. PDBu injection. In contrast, i.t. injection of PDBu produced a delayed but significant increase in signal intensity at 3-6 h in the cingulate cortex, at 4-6 h in the nucleus accumbens
and at 3-6 h in the ventral tegmental area. In addition, all effects of PDBu were abolished in mice that lacked the PKC gamma gene. These results suggest that the activation of spinal PKC gamma associated with the activation of ascending pain transmission may be an important factor in chronic pain-like hyperalgesia with changes in emotionality. (c) 2007 Elsevier Ireland Ltd. All rights reserved.”
“The heat shock response is a genetically well-ordered process for cell to generate heat shock protein (HSP). Various stressors can trigger the response through heat shock transcriptional factor (HSF) regulation. Recent studies demonstrated that preconditioning of N-methyl-D-aspartate (NMDA) at non-lethal levels has neuroprotective effects, but the exact mechanisms are unclear.