Serotonin 5-HT4 receptors and forebrain cholinergic system: receptor expression in identified cell populations

Autor: Raúl Peñas-Cazorla, M. Teresa Vilaró
Přispěvatelé: Ministerio de Ciencia y Tecnología (España), European Commission, Generalitat de Catalunya
Rok vydání: 2014
Předmět:
Zdroj: Digital.CSIC. Repositorio Institucional del CSIC
instname
ISSN: 1863-2661
Popis: © 2014, Springer-Verlag Berlin Heidelberg. Activation of serotonin 5-HT4 receptors has pro-cognitive effects on memory performance. The proposed underlying neurochemical mechanism is the enhancement of acetylcholine release in frontal cortex and hippocampus elicited by 5-HT4 agonists. Although 5-HT4 receptors are present in brain areas related to cognition, e.g., hippocampus and cortex, the cellular localization of the receptors that might modulate acetylcholine release is unknown at present. We have analyzed, using dual label in situ hybridization, the cellular localization of 5-HT4 receptor mRNA in identified neuronal populations of the rat basal forebrain, which is the source of the cholinergic innervation to cortex and hippocampus. 5-HT4 receptor mRNA was visualized with isotopically labeled oligonucleotide probes, whereas cholinergic, glutamatergic, GABAergic and parvalbumin-synthesizing neurons were identified with digoxigenin-labeled oligonucleotide probes. 5-HT4 receptor mRNA was not detected in the basal forebrain cholinergic cell population. In contrast, basal forebrain GABAergic, parvalbumin synthesizing, and glutamatergic cells contained 5-HT4 receptor mRNA. Hippocampal and cortical glutamatergic neurons also express this receptor. These results indicate that 5-HT4 receptors are not synthesized by cholinergic cells, and thus would be absent from cholinergic terminals. In contrast, several non-cholinergic cell populations within the basal forebrain and its target hippocampal and cortical areas express these receptors and are thus likely to mediate the enhancement of acetylcholine release elicited by 5-HT4 agonists.
This research was funded by Plan Nacional I + D+I (Grant sponsor: Ministerio de Ciencia y Tecnología (Spain); Grant sponsor: European Union/European Regional Development Funds; Grant Number: SAF2002-03408). Support from the Generalitat de Catalunya (Grup de Recerca Consolidat 2009SGR220) is also acknowledged. R. P-C was recipient of a predoctoral fellowship from Ministerio de Ciencia y Tecnología)
Databáze: OpenAIRE
Externí odkaz: