van Oosterom A T, Kerkhoven P, Veltkamp J J
Thromb Haemost. 1979 Apr 23;41(2):273-85.
The metabolic rate of prothrombin, factors VII, IX and X, was studied in nine hypothyroid patients. Disappearance rates of the four vitamin-K-dependent factors, called the prothrombin complex, were measured after assumedly complete blocking of their synthesis with adequate doses of a coumarin congener (acenocoumarol). Reappearance rates were assessed by induction of synthesis with high doses of vitamin K1 (phytomenadion) when stable hypocoagulability had been achieved. Normal values for these rates were derived from earlier studies in our laboratory. In hypothyroid patients the rates of both disappearance and reappearance were significantly slower for all factors tested. Practical consequences of these observations are discussed. The initial level of factor-IX activity in all nine patients was substantially lower than in normal individuals. Therapy by thyroxine-substitution led to normal levels of factor-IX. This implies a divergency in the retardation of the breakdown and production rates in hypothyroidism. The reappearance rate was indeed found to be more retarded than the disappearance rate.
对9例甲状腺功能减退患者的凝血酶原、因子VII、IX和X的代谢率进行了研究。在用足量香豆素同类物（醋硝香豆素）假定完全阻断其合成后，测定了这四种维生素K依赖因子（称为凝血酶原复合物）的消失率。当达到稳定的低凝状态时，通过高剂量维生素K1（植物甲萘醌）诱导合成来评估再出现率。这些速率的正常值来自我们实验室早期的研究。在甲状腺功能减退患者中，所有测试因子的消失率和再出现率均明显较慢。讨论了这些观察结果的实际意义。所有9例患者的因子IX活性初始水平均显著低于正常个体。甲状腺素替代治疗使因子IX水平恢复正常。这意味着甲状腺功能减退时分解速率和产生速率的延缓存在差异。实际上发现再出现率比消失率更迟缓。
