While overall tone-evoked response magnitudes were comparable between the two structures, tone signal : noise was significantly greater within the OT than in the PCX. Z-VAD-FMK chemical structure No effect of tone frequency (1–55 kHz) was found within either structure, with most units being narrowly tuned to a single frequency. These results suggest that a major portion of odor-evoked output from the olfactory bulb (i.e. that entering the OT and PCX) is subject to auditory sensory input in a manner that may modulate odor information processing,
odor-guided behaviors and perception. “
“Behavioral rhythms induced by methamphetamine (MAP) and daily restricted feeding (RF) in rats are independent of the circadian pacemaker in the suprachiasmatic nucleus (SCN), and have been regarded to share a common oscillatory mechanism. In the present study, in order to examine the responses of brain oscillatory systems to MAP and RF, circadian rhythms in clock gene, Period2, expression were measured in several brain selleck chemicals llc areas in rats. Transgenic rats carrying a bioluminescence reporter of Period2-dLuciferase were subjected to either daily injection
of MAP or RF of 2 h at a fixed time of day for 14 days. As a result, spontaneous movement and wheel-running activity were greatly enhanced following MAP injection and prior to daily meal under RF. Circadian Per2 rhythms were measured in the cultured brain tissues containing one of the following structures: the olfactory bulb; caudate-putamen; parietal cortex; substantia nigra; and SCN. Except for the SCN, the circadian Per2 rhythms in the brain tissues were significantly phase-delayed by 1.9 h on average in MAP-injected rats as compared with the saline-controls. On the other hand, the circadian rhythms outside the SCN were significantly phase-advanced by 6.3 h on average in rats under RF as compared with those under ad libitum feeding. These findings indicate that the circadian rhythms in specific brain areas of the central dopaminergic system respond differentially to MAP
injection and RF, suggesting that different oscillatory mechanisms in the brain underlie the MAP-induced behavior and pre-feeding activity under RF. “
“Glutamate is the major excitatory neurotransmitter of the central nervous system in vertebrates. Excitotoxicity, caused by over-stimulation Reverse transcriptase of the glutamate receptors, is a major cause of neuron death in several brain diseases, including epilepsy. We describe here how behavioural seizures can be triggered in adult zebrafish by the administration of kainate and are very similar to those observed in rodent models. Kainate induced a dose-dependent sequence of behavioural changes culminating in clonus-like convulsions. Behavioural seizures were suppressed by DNQX (6,7-dinitroquinoxaline-2,3-dione) dose-dependently, whilst MK-801 (a non-competitive NMDA receptor antagonist) had a lesser effect.