Serotonergic median raphe

DahlstrOm A, Fuxe K (1964) Evidence for the existence of monoamine-containing neurons in the central nervous system. Acta Physiol Scand 62 2-55 Daugherty WP, Corley KC, Phan TH, Boadle-Biber MC (2001) Further studies on the activation of rat median raphe serotonergic neurons by inescapable sound stress. Brain Res 923 103-111... 

Mamounas, L.A., and Molliver, M.E. Dual serotonergic projections to forebrain have separate origins in the dorsal and median raphe nuclei Retrograde transport after selective axonal ablation by p-chloroamphetamine (PCA). Abstr Soc Neurosci 13 907, 1987. 

Morin, L. P. 8r Meyer-Bernstein, E. L. (1999). The ascending serotonergic system in the hamster Comparison with projections of the dorsal and median raphe nuclei. Neuroscience 91, 81-105. 

Varga V., Sik A., Freund T. F Kocsis B. (2002). GABA(B) receptors in the median raphe nucleus distribution and role in the serotonergic control of hippocampal... 

These differences may be extremely important in understanding the role of these two distinct serotonergic systems, arising from the dorsal and median raphe nuclei, in normal brain function and in mental illness. 

Lesions of serotonergic neurons in laboratory animals have been reported by some, but not all, investigators to disrupt locomotor rhythms or to result in the loss of the daily rhythm of corticosterone. There is evidence that, in the hamster, the median raphe nucleus projects to the SCN whereas the dorsal raphe nucleus innervates the IGL furthermore, the serotonergic innervation to the SCN and not the IGL is necessary for the photic entrainment of locomotor activity [22]. It appears then, that the SCN circadian pacemaker or clock is modulated by stimulation of serotonergic receptors in the SCN and that serotonergic projections to the SCN may modulate the phase of the SCN in intact animals. 

Figure 5. Serotonergic systems in the human brain with projections to the cerebral cortex from the dorsal raphe nucleus (continuous line) and from the median raph nucleus (dotted line). Projections from more posterior nuclei also as continuous lines.

Kosofsky BE, Molhver ME The serotonergic innervation of cerebral cortex different classes of axon terminals arise from dorsal and median raphe nuclei. Synapse 1 153-168, 1987... 

Mamounas, L.A. and Molliver, M.E. (1988) Evidence for dual serotonergic to neocortex Axons from the dorsal and median raphe are differentially vunerable to the neurotoxin p-cholroamphetamine (PCA). Exp. Neurol, 102, 23-36. 

Fig. 1.4 Diagram of a dorsal view of the brainstem the cerebellum has been removed. The extent of the reticular formation within the brainstem is illustrated. The reticular formation is a polysynaptic network that consists of three regions a series of midUne raphe nuclei (the median reticular formation, which is the site of origin of the major serotonergic pathways in the nervous system) this is flanked bUateraUy by the paramedian reticular formation (an efferent system of magnoceUular neurons with ascending and descending projections) and farthest from the midhne, the lateral reticular formation, consisting of parvoceUular neurons that project transversely See also Color Insert)...

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