Department of Psychology, The University of Tulsa, Tulsa, OK 74104, USA.
Biol Psychol. 2011 Mar;86(3):360-9. doi: 10.1016/j.biopsycho.2011.01.008. Epub 2011 Feb 1.
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.
短等位基因的 5-羟色胺转运体基因（5-HTTLPR）与更大的负性情绪有关。鉴于情绪调节疼痛，短等位基因携带者（s-携带者）也可能表现出改变的疼痛调节。本研究使用了一个经过充分验证的情绪图片观看范式来调节疼痛和伤害性屈反射（NFR，一种衡量脊髓伤害性感受的方法），在 144 名健康的基因分型参与者中进行。正如预期的那样，在不愉快的图片中，疼痛/NFR 反应最大，在愉快的图片中最小。然而，与 l/l-携带者相比，s-携带者在愉快的图片中表现出更大的疼痛抑制，在不愉快的图片中表现出更大的疼痛促进。NFR 的情绪调节和 NFR 阈值均与 5-HTTLPR 多态性无关。结果还表明，s-携带者的男性疼痛阈值和耐受力高于其他参与者。总之，我们的结果表明，5-HTTLPR 多态性可能会影响脊髓以上水平的疼痛调节；然而，对疼痛敏感性的影响可能是性别特异性的。
