同型半胱氨酸水平、MTHFR基因突变与原发性高血压的病例对照研究(英文)

Elevated serum homocysteine,MTHFR gene mutation and essential hypertension in Chinese

探讨升高的同型半胱氨酸水平、ＭＴＨＦＲ基因突变与原发性高血压的关系。方法：从上海一个社区中随机选取１２７例３５～７５岁的原发性高血压病人和１７０例正常血压者。采用聚合酶链反应－限制性片段长度多态性分析ＭＴＨＦＲ基因多态性。使用高效液相色谱结合电化学方法检测血清中同型半胱氨酸总浓度，使用放射免疫法同时测定血清中叶酸和Ｂ_（１２）浓度。结果：调整年龄和性别后，病例和对照组同型半胱氨酸水平分别为 １０．５６ μｍｏｌ／Ｌ和 １０．３４ μｍｏｌ／Ｌ，差异无显著性（Ｐ＝０．６３）。在未服降压药的对象中同型半胱氨酸浓度与收缩压和舒张压亦无关联。该人群ＭＴＨＦＲ不耐热性基因突变频率为１３．１％，突变等位基因频率为３８．７％。病例组与对照组基因型分布和突变等位基因频率无显著性差异。然而，病例组叶酸和Ｂ_（１２）浓度高于对照组。结论：本研究未发现升高的同型半胱氨酸水平、ＭＴＨＦＲ基因突变是原发性高血压的独立危险因素。高血压病人较高的叶酸和Ｂ_（１２）水平可能降低了同型半胱氨酸的危险性。

To examine the relationship between elevated homocysteine levels,mutation of the MTHFR 677 C to T and essential hypertension in a Chinese population,a community-based case-control study was conducted. Methods: 127 essential hypertension patients of age 35 to 75 were randomly selected from a community. 170 control subjects with blood pressure <140/90 mmHg were selected from the same community. MTHFR genotypes were identified by PCR and restriction fragment length polymorphism analysis with Hinf I digestion. Serum homocysteine was determined using HPLC. Folate and vitamin B_(12) were measured by radioimmunoassay. Results: After adjusting for age and sex, the mean homocysteine level was 10. 56 μmol/L for hypertensive patients and 10. 34 μmol/L for controls (P = 0. 63 ). No association between either SBP or DBP and Hey concentration was found in subjects without anti-hypertensive medications. The prevalence of homozygousity for thermolabile MTHFR variant for this population was 13. 1 %,and the mutant allele frequency was 38. 7%. There was no significant difference on genotype distributions and the mutant allele frequency for two groups studied. However,the concentrations of folate and B_(12) for the hypertensive subjects were generally higher than the controls. Conclusions:The present study didn't find that elevated Hcy levels or MTHFR mutation are independent risk factors for essential hypertension. The higher folate and B_(12) in the hypertensive subjects might contribute to lower the risk of homocysteine.