title: Expression of Serotonin2C Receptors in Pyramidal and GABAergic Neurons of Rat Prefrontal Cortex: A Comparison with Striatum.
abstract: The prefrontal cortex (PFC) is enriched in several serotonin receptors, including 5-HT1A-R, 5-HT2A-R, and 5-HT3-R. These receptors modulate PFC activity due to their expression in large neuronal populations (5-HT1A-R, 5-HT2A-R) or in selected GABAergic populations (5-HT3-R). They are also relevant for antidepressant and antipsychotic drug action. Less is known about the localization of 5-HT2C-R, for which atypical antipsychotics show high affinity. Here, we report on the cellular distribution of 5-HT2C-R in rat PFC and striatum, using double in situ hybridization histochemistry. In PFC, 5-HT2C-R are expressed in pyramidal (VGLUT1-positive) and GABAergic (GAD-positive) neurons, including parvalbumin-positive neurons. There is a marked dorso-ventral gradient in the proportion of VGLUT1-positive cells expressing 5-HT2C-R (9% in the cingulate cortex, 61% in the tenia tecta and 66% in the piriform cortex), less marked for GABAergic neurons (13-27%). There is also a laminar gradient, with more cells expressing 5-HT2C-R in deep (V-VI) than in intermediate (II-III) layers. In common with 5-HT3-R, layer I GABAergic cells express 5-HT2C-R. The proportion of 5-HT2C-R-expressing striatal neurons was 23% (dorsolateral caudate-putamen), 37% (ventromedial caudate-putamen), 53% (nucleus accumbens-core), and 49% (nucleus accumbens-shell). These results help to better understand the serotonergic modulation of PFC-based networks, including basal ganglia circuits, and atypical antipsychotic drug action.
authors.affiliation: Institut d'Investigacions Biomèdiques de Barcelona (IIBB), Consejo Superior de Investigaciones Científicas (CSIC), Spain.|Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain.
authors.forename: Noemí
authors.initials: N
authors.lastname: Santana
authors.affiliation: Institut d'Investigacions Biomèdiques de Barcelona (IIBB), Consejo Superior de Investigaciones Científicas (CSIC), Spain.|Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Madrid, Spain.|Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Spain.
authors.forename: Francesc
authors.initials: F
authors.lastname: Artigas
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001931:Brain Mapping; D003342:Corpus Striatum / Q000166:cytology*; D059330:GABAergic Neurons / Q000378:metabolism*; D005968:Glutamate Decarboxylase / Q000378:metabolism; D008297:Male; D010320:Parvalbumins / Q000378:metabolism; D017397:Prefrontal Cortex / Q000166:cytology*; D017966:Pyramidal Cells / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D044405:Receptor, Serotonin, 5-HT2C / Q000235:genetics / Q000378:metabolism*; D050598:Vesicular Glutamate Transport Protein 1 / Q000378:metabolism
chemical_list: D010320:Parvalbumins; D012333:RNA, Messenger; D044405:Receptor, Serotonin, 5-HT2C; C493466:Slc17a7 protein, rat; D050598:Vesicular Glutamate Transport Protein 1; D005968:Glutamate Decarboxylase; C402565:glutamate decarboxylase 1
keywords: 5-HT2C receptors; GABA interneurons; atypical antipsychotic drugs; prefrontal cortex; pyramidal neurons