Serotonin innervation of the primate suprachiasmatic nucleus

• Published in: Brain research Vol. 1010; no. 1; pp. 169 - 173
• Main Authors: Moore, Robert Y, Speh, Joan C
• Format: Journal Article
• Language: English
• Published: London Elsevier B.V 04.06.2004; Amsterdam Elsevier; New York, NY
• Subjects: Aged; Aged, 80 and over; Animals; Biological and medical sciences; Carrier Proteins - metabolism; Central nervous system; Central neurotransmission. Neuromudulation. Pathways and receptors; Circadian rhythm; Cynomologous monkey; Ependyma - cytology; Ependyma - metabolism; Female; Fundamental and applied biological sciences. Psychology; Human; Humans; Immunohistochemistry; Macaca fascicularis; Male; Membrane Glycoproteins - metabolism; Membrane Transport Proteins; Nerve Tissue Proteins - metabolism; Neural Pathways - cytology; Neural Pathways - metabolism; Presynaptic Terminals - metabolism; Raphe; Raphe Nuclei - cytology; Raphe Nuclei - metabolism; Retinohypothalamic tract; Serotonin - metabolism; Serotonin Plasma Membrane Transport Proteins; Suprachiasmatic Nucleus - cytology; Suprachiasmatic Nucleus - metabolism; Supraependymal plexus; Third Ventricle - cytology; Third Ventricle - metabolism; Vasoactive Intestinal Peptide - metabolism; Vasoactive intestinal polypeptide; Vertebrates: nervous system and sense organs; Visual Pathways - cytology; Visual Pathways - metabolism; Human; Retinohypothalamic tract; Vasoactive intestinal polypeptide; Supraependymal plexus; Circadian rhythm; Neural basis of behavior; Cynomologous monkey; Raphe; Suprachiasmatic nucleus; Serotonin; Innervation; Central nervous system; Monkey; Biological rhythm; Hypothalamus; Encephalon; Vertebrata; Mammalia; Vasoactive intestinal peptide; Neurotransmitter; Primates
• ISSN: 0006-8993; 1872-6240
• DOI: 10.1016/j.brainres.2004.02.024

The suprachiasmatic nucleus (SCN) in rodents receives a dense innervation from serotonin neurons of the midbrain raphe. This projection overlaps the terminal field of the retinohypothalamic tract in the SCN core, the central part of the nucleus characterized by a population of vasoactive intestinal polypeptide (VIP)-containing neurons. To determine whether a similar pathway is present in primates, we carried out an immnunocytochemical investigation of the primate SCN using antisera against either serotonin (monkey) or the serotonin transporter (human). This demonstrated a dense serotonergic plexus over the SCN core in both species. As in rodents, the distribution of the serotonin innervation of the primate SCN overlaps that of the retinohypothalamic input and the VIP neuronal population. We also find a supraependymal plexus of serotonin axons in the third and lateral ventricles of the human and monkey brains that is similar in distribution, but less dense, than the one reported in rodents.