acetylcholin, response inhibition and attention (ARA-study)

People showing symptoms of attention deficit hyperactivity disorder (ADHD) often present an impairment of reaction time and response inhibition. These executive functions are influenced by nicotinergic acetylcholine receptors (nAchr) as mediators of cholinergic signalling, and show differences between both sexes. We examined the effects of two functional polymorphismsrs3841324 (S/L) and rs16969968 (G/A) of the α5 subunit encoding gene CHRNA5, ADHD symptoms and sex on response inhibition/reaction time in the Stop Signal Task. In the analyses, 183 participants (52.4 % females) were included. In participants carrying the diplotype (SS_GG), men with ADHD symptoms responded faster, while men without ADHD symptoms were slower than women (F = 5.313; p = 0.023; η² = 0.034). Although explorative, this threefold interaction on reaction time but not response inhibition extend previous findings, suggesting a moderating effect of the CHRNA5 diplotype SS_GG in male carriers with ADHD symptoms and might inspire research on genotype- and gender-specific ADHD medication.

注意缺陷多动障碍（ADHD）患者常表现出反应时间受损和反应抑制障碍。这些执行功能受作为胆碱能信号传导介质的烟碱型乙酰胆碱受体（nAchr）影响，且在两性间存在差异。我们在停止信号任务（Stop Signal Task）中，考察了编码α5亚基的CHRNA5基因的两个功能性多态性位点rs3841324（S/L）和rs16969968（G/A）、ADHD症状及性别对反应抑制/反应时间的影响。分析共纳入183名参与者（女性占52.4%）。携带双倍型（diplotype）（SS_GG）的参与者中，有ADHD症状的男性反应更快，而无ADHD症状的男性反应慢于女性（F=5.313；p=0.023；η²=0.034）。尽管本研究为探索性研究，但这种仅针对反应时间而非反应抑制的三重交互作用（threefold interaction）拓展了既往研究发现，提示CHRNA5基因SS_GG双倍型对具有ADHD症状的男性携带者存在调节效应（moderating effect），并可能为基因型和性别特异性ADHD药物研究提供启发。