The dorsal raphe nucleus and its serotonin-releasing neurons are thought to regulate motivation and reward-seeking. These neurons are known to be active during motivated behavior, but the underlying principles that govern their activity are unknown. Here we show that a group of dorsal raphe neurons encode behavioral tasks in a systematic manner, tracking progress toward upcoming rewards. We ana...

The Cholinergic and GABAergic .bers of the medial septal/diagonal band of Broca (MS/DB) area project to the hippocampus and constitute the septo-hippocampal pathway, which has been proven to play a role in learning and memory. In addition, the hippocampus has bidirectional connections with the septum so that to self-regulate of cholinergic input. The activity of septal and hippocampal neuron...

The nucleus paragigantocellularis (PGI) is located in the rostral ventrolateral medulla and has noticeable connections with some other brain nuclei, such as locus ceruleus, nucleus raphe magnus and periaqueductal gray. In rats it is 3 mm in rostrocaudal and 1 mm in mediolateral and 1 mm in the dorsolateral aspect. Anatomically and functionally, PGI has been divided into two subnuclei, retrofaci...

We used double-label in situ hybridization to examine the cellular localization of 5-ht(5B) receptor mRNA in relation to serotonin transporter mRNA in the rat dorsal raphe (DR) and central superior nucleus (CS, median raphe nucleus). 5-ht(5B) receptor mRNA hybridization signal was often found on serotonin transporter mRNA-positive neuron profiles. The degree of cellular colocalization of these ...

The distribution of adrenocorticotropin hormone/corticotropin-like intermediate lobe peptide was studied in the cat brain stem, using an indirect immunoperoxidase technique. No immunoreactive cell bodies were observed. However, a high density of immunoreactive fibers was found in the periaqueductal gray, the dorsal nucleus of the raphe, the locus coeruleus, and the marginal nucleus of the brach...

Horseradish peroxidase (HRP) was injected to various parts of the amygdala in 50 rats. Retrograde axonal transport revealed that tegmental areas containing biogenic amines: dorsal and median raphe nuclei, locus coeruleus and ventral tegmental area, project diffusely to various amygdaloid areas. Moreover, HRP labeled cells were found in the parabrachial nucleus (following injection of the latera...

The consequences of the absence of 5-HT reuptake on the functional properties of 5-HT(1A) receptors were examined in the dorsal raphe nucleus and the hippocampus of knock-out mice lacking the serotonin transporter (5-HTT). Extracellular recordings showed that application of selective 5-HT reuptake inhibitors such as paroxetine and citalopram onto brainstem slices resulted in a concentration-dep...