1 Cardiovascular Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran (Islamic Republic of)
2 Non-Communicable Diseases Research Center, Endocrinology and Metabolism Population Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran (Islamic Republic of). Students’ Scientific Research Center (SSRC), Tehran University of Medical Sciences, Tehran, Iran (Islamic Republic of)
Background. Recent studies have confirmed the essential and paramount role of the L-Citrulline on the nitric oxide regulation and the endothelial function improvement.
Materials and Methods. In this cross-over clinical trial, thirty patients, diagnosed with coronary artery disease (CAD) and flow mediated dilation to nitroglycerin dependent vasodilation (FMD/NMD) ratio less than 1, were included. The patients were randomly divided into two groups of 15 patients and underwent treatment by L-Citrulline or placebo for 15 days, in 2 step protocol. The indicators of assessment in the current study were the ratio of the FMD/NMD and FMD value.
Results. In the current cross-over clinical trial, the mean of FMD to NMD ratio and mean FMD value of all patients before starting the protocol were 0.91 ± 0.08 and 4.04 ± 0.51 mm, respectively. The final results of study showed that following L-Citrulline administration, mean FMD to NMD ratio and mean FMD value were enhanced to: 1.03 ± 0.09 and 4.96 ± 0.72 mm, respectively, which were statistically significant (P<0.001 and P<0.001, respectively). However, following placebo administration, mean FMD to NMD ratio and mean FMD value were receded to: 0.92 ± 0.09 and 4.06 ± 0.22 mm, respectively, which were not statistically significant (P = 0.75 and P = 0.89, respectively). Moreover, the improvement of mean FMD to NMD ratio (0.12 ± 0.02) and mean FMD value (0.92 ± 0.16 mm), following L-Citrulline administration, were statistically significant in comparison with the change of mean FMD to NMD ratio (0.01 ± 0.002) and mean FMD value (0.02 ± 0.003), following placebo administration (P<0.001 and P<0.001, respectively).
Conclusion. L-Citrulline treatment can lead to improvement of the endothelial function in patients diagnosed with CAD which are assessed via FMD to NMD ratio FMD value enhancements.
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