Patients suffering from BPD are less heat pain sensitive independent of the <i>val158met</i> polymorphism.

<p>(A) Genotype distribution of the <i>val158met</i> polymorphism in healthy controls (open) and BPD patients (filled bars) do not differ. (B) Heat pain perception was markedly reduced in BPD. Dose-response function in the pretest session (circles) and stimulus temperatures applied during fMRI (squares) did significantly differ between controls and BPD (ns p>0.4; * p<0.05; ** p<0.01; *** p<0.001, students t-test).</p

Association between COMT genotype and pain sensitivity.

<p>A: Lower heat pain perception in BPD in response to 43°C does not depend upon the <i>val158met</i> polymorphism. ^ns p>0.3, BPD and control, respectively; * p<0.05; ** p<0.01, students t-test. B: Stimulus temperatures for the induction of a heat pain sensation of NRS 40 decreases with the number of met alleles in healthy volunteers but not in BPD patients (ns p>0.19; (*) p<0.1; * p<0.05, students t-test).</p

Group-specific regression analyses.

<p>Group-specific regression analyses.</p

Brain areas activated in response to subjectively adjusted heat pain correlate with COMT val158met polymorphism.

<p>During subjectively similar intense heat pain perception (individual temperature in BPD 43°C in healthy controls), posterior parietal cortex (A), lateral globus pallidus (LGP; B) and the posterior cingulate cortex (PPC; C) displayed significant correlation with COMT-polymorphism. Labelling as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0023658#pone-0023658-g002" target="_blank">Fig. 2</a>,* p<0.05.</p

Association between COMT genotype and fMRI activation during painful stimulation in frontal brain areas.

<p>Significant correlations were observed for both stimulus conditions within the dorsolateral prefrontal cortex (DLPFC; A,B). Furthermore, the posterior parietal cortex (PPC; C) and the lateral globus pallidus (LGP; D) also displayed significant correlation during both conditions. Statistics and regression lines for group means are shown in gray (all 50 subjects), black (BPD), and dashed (Control), respectively; significant Pearson product moment correlation * p<0.05, ** p<0.01, *** p<0.001, versus r = 0.</p