Elevated methionine in young Tg-I278T Cbs^−/− mice does not alter risk for microvessel thrombosis. Plasma levels of (A) tHcy and (B) methionine were measured in 3-week-old mice. (C) The time to first occlusion or stable occlusion was examined in mesenteric arterioles after chemical injury. (D) The percentage of mice with a patent mesenteric arteriole as a function of time after chemical injury. Seven mice were studied in each group. Values are mean ± SE; **P < .001 and *P < .01 compared with Tg-I278T Cbs^+/+ mice.