title: Serotonin transporter gene (5-HTTLPR) polymorphisms are associated with emotional modulation of pain but not emotional modulation of spinal nociception.
abstract: The short allele of the serotonin transporter gene (5-HTTLPR) is associated with greater negative emotionality. Given that emotion modulates pain, short allele carriers (s-carriers) may also demonstrate altered pain modulation. The present study used a well-validated emotional picture-viewing paradigm to modulate pain and the nociceptive flexion reflex (NFR, a measure of spinal nociception) in 144 healthy genotyped participants. As expected, pain/NFR responses were largest during unpleasant pictures and smallest during pleasant pictures. However, relative to l/l-carriers, s-carriers demonstrated greater pain inhibition during pleasant pictures and greater pain facilitation during unpleasant pictures. Neither emotional modulation of NFR nor NFR threshold was associated with 5-HTTLPR polymorphisms. Results also indicated that men who were s-carriers had a higher pain threshold and tolerance than other participants. Taken together, our results indicate 5-HTTLPR polymorphisms may influence pain modulation at the supraspinal (not spinal) level; however, the influence on pain sensitivity may be sex-specific.
authors.affiliation: Department of Psychology, The University of Tulsa, Tulsa, OK 74104, USA.
authors.forename: Shreela
authors.initials: S
authors.lastname: Palit
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Sheaff
authors.forename: Christopher R
authors.initials: CR
authors.lastname: France
authors.forename: Sarah T
authors.initials: ST
authors.lastname: McGlone
authors.forename: William T
authors.initials: WT
authors.lastname: Potter
authors.forename: Allan R
authors.initials: AR
authors.lastname: Harkness
authors.forename: John L
authors.initials: JL
authors.lastname: McNulty
authors.forename: Emily J
authors.initials: EJ
authors.lastname: Bartley
authors.forename: Rachel
authors.initials: R
authors.lastname: Hoffmann
authors.forename: Julie K
authors.initials: JK
authors.lastname: Monda
authors.forename: Jamie L
authors.initials: JL
authors.lastname: Rhudy
mesh_terms: D000328:Adult; D000367:Age Factors; D000704:Analysis of Variance; D001143:Arousal; D004558:Electric Stimulation / Q000009:adverse effects; D004644:Emotions / Q000502:physiology*; D005260:Female; D055106:Genome-Wide Association Study / Q000379:methods; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D009619:Nociceptors / Q000502:physiology; D010146:Pain / Q000235:genetics* / Q000503:physiopathology*; D010147:Pain Measurement / Q000379:methods; D017288:Pain Threshold / Q000523:psychology; D010775:Photic Stimulation / Q000379:methods; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D011930:Reaction Time / Q000235:genetics; D012018:Reflex / Q000235:genetics; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*; D012737:Sex Factors; D013116:Spinal Cord / Q000503:physiopathology*; D013497:Sural Nerve / Q000502:physiology; D011795:Surveys and Questionnaires; D055815:Young Adult
chemical_list: D050486:Serotonin Plasma Membrane Transport Proteins