title: Association of 5-HT1B receptor polymorphisms with the loudness dependence of auditory evoked potentials in a community-based sample of healthy volunteers.
abstract: The terminal autoreceptor 5-HT1B is centrally involved in the regulation of the brain serotonergic system and in several psychiatric disorders including depression, addiction, and obsessive-compulsive disorder. The loudness dependence of the auditory evoked N1/P2-component (LDAEP; primary auditory cortex) is currently considered as one of best-validated indicators of serotonergic neurotransmission, especially for synaptically released serotonin. Since the 5-HT1B receptor is involved in the release of serotonin at terminal endings of cortical neurons, this study addressed the question whether single nucleotide polymorphism (SNP) in the gene coding for this receptor (HTR1B) are related to LDAEP of the primary auditory cortex (tangential dipole) investigating a community-based sample of 127 healthy subjects randomly selected from the general population. In this carefully recruited sample, a G-G haplotype (rs1213368-rs6296) and the respective G-alleles were found to be related to a strong LDAEP response of the left tangential dipole, indicating low serotonergic activity. Apart from the fact that this is the first study which relates HTR1B SNPs to a measure of serotonergic function, it can be speculated that LDAEP may reflect parts of the release mechanism of serotonin at cortical synapses, although the lateralized finding cannot be entirely explained. Carriers of the G-alleles may be characterized by a particularly strong feedback inhibition of serotonin release at cortical terminals in the primary auditory cortex, possibly mediated by higher sensitivity of 5-HT1B receptors associated with low serotonergic activity.
authors.affiliation: Department of Psychiatry, Ruhr-University Bochum, Alexandrinenstrasse 1, 44791 Bochum, Germany. georg.juckel@wkp-lwl.org
authors.forename: Georg
authors.initials: G
authors.lastname: Juckel
authors.forename: Ulrich
authors.initials: U
authors.lastname: Hegerl
authors.forename: Ina
authors.initials: I
authors.lastname: Giegling
authors.forename: Paraskevi
authors.initials: P
authors.lastname: Mavrogiorgou
authors.forename: Alexander
authors.initials: A
authors.lastname: Wutzler
authors.forename: Christiane
authors.initials: C
authors.lastname: Schuhmacher
authors.forename: Idun
authors.initials: I
authors.lastname: Uhl
authors.forename: Martin
authors.initials: M
authors.lastname: Brüne
authors.forename: Christoph
authors.initials: C
authors.lastname: Mulert
authors.forename: Oliver
authors.initials: O
authors.lastname: Pogarell
authors.forename: Dan
authors.initials: D
authors.lastname: Rujescu
mesh_terms: D000161:Acoustic Stimulation; D000483:Alleles; D004813:Epidemiology; D005072:Evoked Potentials, Auditory / Q000235:genetics*; D005858:Germany; D006239:Haplotypes; D011110:Polymorphism, Genetic; D044302:Receptor, Serotonin, 5-HT1B / Q000235:genetics* / Q000502:physiology; D012701:Serotonin / Q000378:metabolism
chemical_list: D044302:Receptor, Serotonin, 5-HT1B; D012701:Serotonin