02630nas a2200253 4500008004100000245008100041210006900122260001600191300001200207490000600219520186200225653002202087653002602109653001802135653001702153653001702170100002502187700001902212700001802231700002202249700002102271700002002292856006402312 2014 eng d00aEffects of L-citrulline Diet on Stress-induced Cold Hypersensitivity in Mice0 aEffects of Lcitrulline Diet on Stressinduced Cold Hypersensitivi cAugust,2014 a297-3020 v63 a

Background: L-citrulline is an amino acid discovered in watermelon (Citrullus lanatus, Cucurbitaceae) and is a known component of the nitric oxide (NO) cycle that plays an important role in adjusting blood circulation and supplying NO and a key component of the endothelium-derived relaxing factor. Objective: The objective of this study is to evaluate the effect of L-citrulline on a newly established stress-induced cold hypersensitivity mouse model. Materials and Methods: When normal mice were forced to swim in water at 25°C for 15 min, their core body temperature dropped to 28.9°C, and then quickly recovered to normal temperature after the mice were transferred to a dry cage at room temperature (25°C). A 1-h immobilization before swimming caused the core body temperature to drop to ca. 24.1°C (4.8°C lower than normal mice), and the speed of core body temperature recovery dropped to 57% of the normal control. We considered this delay in recovery from hypothermia to be a sign of stress-induced cold hypersensitivity. Similar cold hypersensitivity was induced by administration of 50 mM L-NG-nitroarginine methyl ester, a NO synthesis inhibitor. Results: In this study, we showed that recovery speed from the stress-induced hypothermia remarkably improved in mice fed a 1% L-citrulline-containing diet for 20 days. Furthermore, the nonfasting blood level of L-arginine and L-citrulline increased significantly in the L-citrulline diet group, and higher serum nitrogen oxide levels were observed during recovery from the cold. Conclusions: These results suggested that oral L-citrulline supplementation strengthens vascular endothelium function and attenuates stress-induced cold hypersensitivity by improving blood circulation.

10aCitrullus lanatus10aCold hypersensitivity10aCucurbitaceae10aL-citrulline10aNitric oxide1 aKobayashi, Yoshinori1 aNarita, Kazuki1 aChiba, Kotaro1 aTakemoto, Hiroaki1 aMorita, Masahiko1 aMorishita, Koji uhttps://phcogres.com/article/2014/6/4/1041030974-8490138269