Distribution of Serotonin Receptor of Type 6 (5-HT6) in Human Brain Post-mortem. A Pharmacology, Autoradiography and Immunohistochemistry Study

作者：Marazziti Donatella^*; Baroni Stefano; Pirone Andrea; Giannaccini Gino; Betti Laura; Schmid Lara; Vatteroni Elena; Palego Lionella; Borsini Franco; Bordi Fabio; Piano Ilaria; Gargini Claudia; Castagna Maura; Catena Dell' Osso Mario; Lucacchini Antonio

来源：Neurochemical Research, 2012, 37(5): 920-927.

DOI：10.1007/s11064-011-0684-y

• Serotonin
• Serotonin receptors
• Serotonin receptors of type 6
• Human brain
• Autopsy
• [I-125]SB-258585 binding
• Autoradiography
• Immunohistochemistry
• Immunofluorescence

The aim of this study was to investigate the distribution of serotonin (5-HT) receptors of type 6 (5-HT6) in postmortem human prefrontal cortex, striatum and hippocampus. The brain samples were obtained from 6 subjects who had died for causes not involving primarily or secondarily the CNS. The 5-HT6 receptor distribution was explored by the [I-125]SB-258585 binding to brain membranes followed by the pharmacological characterization, where possible, and by autoradiographic, immunohistochemical and immunofluorescence evaluations. A specific and saturable [I-125]SB-258585 binding was detected in striatum only, with a pharmacological characterization consistent with that of a 5-HT6 receptor. The autoradiography showed the presence of a specific [I-125]SB-258585 binding distributed homogeneously in caudate, putamen and accumbens. The immunohistochemistry, carried out in the striatum only, coupled with the immunofluorescence with glial fibrillary acidic protein (GFAP) and parvalbumin (PV) showed the co-localization of 5-HT6 receptor with PV, while indicating that this receptor subtype was expressed in neurons and not in astrocytes. Taken together, the present findings showed the presence of a higher density of 5-HT6 receptors, as labeled by [I-125]SB-258585, in striatum than in hippocampus and prefrontal cortex, and specifically within the neuronal body. In addition, they would suggest that striatum is one of the major potential CNS targets linked to 5-HT6 receptor modulation.

• 出版日期2012-5