Plasma tHcy and sensitivity of FV to APC in human volunteers.

(A) Plasma tHcy levels after oral administration of L-methionine (open circles) or placebo (solid circles). (B) Plasma was collected 6 hours after oral administration of L-methionine (open triangles) or placebo (solid circles). Samples were diluted 1:10 in human FV–deficient plasma, and APTT was measured in the presence of the indicated concentrations of human APC. Values are mean ± SE.