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Abbreviation for homocysteine.

homocysteine (HCY) test

a blood test used to detect levels of homocysteine, which, if increased, may act as an independent risk factor for ischemic heart disease, cerebrovascular disease, peripheral arterial disease, and venous thrombosis. This test should be considered for screening in individuals with progressive and unexplained atherosclerosis despite normal lipoproteins and in the absence of other risk factors and in those with an unusual family history of atherosclerosis.




HSCH2CH2CH(NH2)COOH; an amino acid produced by the catabolism of methionine. With serine, it forms a complex that eventually produces cysteine and homoserine. There is evidence that a high level of homocysteine in the blood may be associated with an increased risk of developing atherosclerosis. Although blood homocysteine levels may be lowered by eating foods rich in folic acid, e.g., green leafy vegetables and fruits, and by vitamin pills containing folic acid and vitamin B6 or B12, research has failed to show that any of these causes a significant reduction in cardiovascular disease.
References in periodicals archive ?
Frozen blood spot stability was assessed by the analysis of 2 controls enriched with MMA, MCA, and HCY at 7.
3B) decreased with increasing HCY plasma concentrations at the distal femur and the lumbar spine.
Although the mean HCY concentration in the methionine group was similar to that reported by others (17) (27.
Moreover, the existence of a recent study from Sweden (n = 996 women), which could not demonstrate a significant increase of fracture risk in individuals with high HCY concentrations, has to be mentioned (12).
Our findings seem to be in contrast to clinical studies, where no or only weak relations were found between circulating HCY and bone mineral density (6,10,24-26).
Therefore, because HCY is produced from methionine, low HCY concentrations may be expected in CSF, but the detected amount of CSF-HCY is 0.
We showed that lower concentrations of serum folate may predict higher concentrations of HCY in CSF (Table 2).
Day-to-day imprecision (CV) for HCY was <5% in serum (at 8.
Concentrations of HCY and related biomarkers in blood and CSF are presented in Table 1.
Results of TRAP and CP-K activity measurements from each donor are expressed as a percentage of the corresponding control activity (mean of 8 control wells without addition of HCY, cysteine, or glutathione).
We therefore expressed TRAP activity as a percentage of controls, using the mean absorbance of control cultures without HCY (n = 8 per individual) as 100%.
TRAP activity increased with increasing HCY concentrations (P <0.