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==构造==

维生素K皆有醌结构，而维生素K₂的命名取决于上图化学式中n的数目。例如当n为4，名称就是MK-4。维生素K₂于身体中的传输会受其结构影响。

研究指出长期口服抗凝剂减少体内正常[[骨钙素]]，从而影响[[骨骼]]健康。这可能导致骨骼矿化不足（[[骨质减少]]）、容易[[骨折]]等<ref>Caraballo PJ, Gabriel SE, Castro MR, Atkinson EJ, Melton LJ 3rd. Changes in bone density after exposure to oral anticoagulants: a meta-analysis.Osteoporos Int. 1999;9(5):441-8.</ref>。另外长期口服抗凝剂亦相信会令小童、成人出现不良的软组织[[钙化]]<ref>Barnes C, Newall F, Ignjatovic V, Wong P, Cameron F, Jones G, Monagle P. Reduced bone density in children on long-term warfarin. Pediatr Res. 2005;57(4):578-81.</ref><ref>Hawkins D, Evans J. Minimising the risk of heparin-induced osteoporosis during pregnancy. Expert Opin Drug Saf. 2005;4(3):583-90</ref>，这是由于缺乏维生素K导致正常[[基质]]Gla[[蛋白]]偏少。在动物实验中血管钙化可出现于服用[[华法林]]两周内<ref>Price [[PA]], Faus SA, Williamson MK. [[Warfarin]] causes rapid calcification of the elastic lamellae in rat arteries and heart valves. Arterioscler Thromb Vasc Biol. 1998;18(9):1400-7.</ref>。另外长期口服抗凝剂的病人被发现其[[动脉]]钙化的程度为其他病人的一倍<ref>Schurgers LJ, Aebert H, Vermeer C, Bültmann B, Janzen J. Oral anticoagulant treatment: friend or foe in cardiovascular disease? Blood. 2004 15;104(10):3231-2.</ref><ref>Koos R, Mahnken AH, Mühlenbruch G, Brandenburg V, Pflueger B, Wildberger JE, Kühl [[HP]]. Relation of oral anticoagulation to cardiac valvular and coronary calcium assessed by multislice spiral computed tomography. Am J Cardiol. 2005;96(6):747-9.</ref>。动脉钙化亦可能导致收缩期[[高血压]]、[[心室肥大]]等<ref>Zieman SJ, Melenovsky V, Kass DA. Mechanisms, pathophysiology, and therapy of arterial stiffness. Arterioscler Thromb Vasc Biol. 2005;25(5):932-43.</ref><ref>Raggi P, Shaw LJ, Berman DS, Callister TQ. Prognostic value of coronary artery calcium screening in subjects with and without diabetes. J Am Coll Cardiol. 2004;43(9):1663-9.</ref>。虽然大量维生素K降低抗凝剂的效用，但现在正研究将抗凝剂疗程及维生素K结合。

==外部连结==

[[分类:维生素K]]

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