Thermolabile 5,10-methylenetetrahydrofolate reductase as a cause of mild hyperhomocysteinemia

摘要: Summary Thermolability of 5,10-methylenetetrahydrofolate reduc­ tase (MTHFR) was examined as a possible cause mild hyperhomocysteinemia in patients with premature vascu­ lar disease. Control subjects and vascular normohomocysteinemia were studied. The mean (±SD) specific MTHFR activity lymphocytes 22 control 15.6 (±4.7) nmol CH20 /m g protein/h (range: 9.1-26,6), the residual after heat inactivation for 5 min at 46°C 55.3 (±12.0)% 35.9-78.3). By measurement activity, two distinct subgroups hyperhomocysteinemic became evident. One group (n - 11) had thermolabile 8.7 (±2.1) pro­ tein/h 5.5 -12.7) inactivation, ranging from 0% to 33%. other = 28) normal 21.5 (±7.2) 10.0-39.0) nor­ mal 53.8 (±9.2)% 33.171.5) ac­ tivity 29 normohomocysteinemic 20.7 (±6.5) 9.4-33.8), 58.2 (±10.2)% 43.0-82.0). Thus, 28% disease, abnormal homocysteine metabolism could be at­ tributed MTHFR.