Blood citrulline concentration during follow-up of Huntington’s disease (HD) patients.

<p>Blood citrulline concentration was measured every 6 months and was compared at each time point with the concentration in non-HD controls (dotted line). The N value in the bar represents the number of collected data at each point (A). All data were normalized to the baseline value and show the progression pattern (B). Data are presented as mean ± standard deviation, *<i>p</i> < 0.05, ***<i>p</i> < 0.001 by <i>t</i> test.