ABC | Volume 113, Nº2, August 2019

Original Article Casonatto et al. Citrulline and post-exercise hypotension Arq Bras Cardiol. 2019; 113(2):218-228 Figure 3 – Individual changes – Diastolic blood pressure. Dashed line: MDC (minimal detectable change). 31 28 5 33 36 21 3 39 38 26 35 1 12 30 17 2 32 18 19 22 11 10 8 7 15 40 13 9 23 6 14 16 25 24 27 34 29 37 4 20 3 28 36 31 20 5 39 21 38 12 26 1 35 37 27 18 19 22 11 2 10 8 7 32 23 15 9 14 6 16 40 25 13 24 17 34 30 29 33 4 3 28 36 5 31 20 39 21 38 12 30 1 37 35 17 22 11 18 19 2 7 8 10 32 23 15 9 14 16 6 25 40 13 24 27 34 29 26 33 4 28 5 36 31 3 20 39 33 12 37 30 38 27 35 17 34 22 7 11 18 19 2 8 32 10 23 15 40 16 14 24 6 25 13 9 1 29 26 21 4 Control-Placebo Control-Citrulline Exercise-Placebo Exercise-Citrulline Diastolic Blood Pressure – Individual Variation –20 –10 0 20 10 60min –30 –40 –20 –10 0 10 Asleep –20 –30 –10 0 10 (mmHg) 24hours –10 –20 –30 0 20 Awake citrulline supplementation was not related to lower prevalence of non-responders. Previous studies have demonstrated that the acute ingestion of citrulline increased NO synthesis, but endothelium-mediated vasodilation was not improved in older adults with heart failure. 37 Recent studies have evaluated endothelial function after some days of citrulline supplementation. Bailey et al., 38 found increases in nitrite levels (21%) after 7 days of citrulline supplementation in healthy young men. Likewise, oral citrulline supplementation (6 g/day) for 7 days increased plasma nitrate levels by 37% in middle-aged men with increased arterial stiffness. 39 Evidence suggests that resting BP level may influence the hypotensive effect of citrulline supplementation. For instance, previous study found decreases in BP (7/3mmHg) after 8 weeks of citrulline supplementation (6 g/day) in prehypertensive and hypertensive obese postmenopausal women. 40 Therefore, we suppose that citrulline supplementation (without exercise) can induce vasodilation only after some weeks. 225