Lewczuk P, Reiber H, Ehrenreich H
Neurochemistry Laboratory, University of Göttingen, Germany.
Neurochem Res. 1998 Aug;23(8):1027-30. doi: 10.1023/a:1020747716815.
In spite of the fact that prothrombin is produced by cells within the central nervous system, its presence in the cerebrospinal fluid (CSF) has not been investigated. We determined the concentration of prothrombin in CSF with reference to the concentration in plasma in paired samples from 18 "normal" control patients and 4 patients with relapsing-remitting type of multiple sclerosis (MS). The newly developed ELISA was very specific (no cross-reactivity with thrombin) and sensitive (detection limit--0.7 ng/ml) with an imprecision of CV = 8.3% (intraseries) and 7.0% (interassay). The mean prothrombin concentration in normal CSF was 0.55 mg/l (CV +/- 33%, range: 0.28-0.93 mg/l), in normal plasma 121.8 mg/l +/- 21%, resulting in a mean CSF/plasma concentration quotient (Q(Proth)--4.5 x 10(-3) (CV +/- 35%, range: 2.1-8.3 x 10(-3)) corresponding to a mean albumin quotient in this group of subjects of Q(Alb) = 5.8 x 10(-3). Due to the Q(Proth) and the molecular weight of prothrombin (72 kDa)--similar to that of albumin--we conclude that prothrombin in normal human CSF originates predominantly (>95%) from blood. The enzymatic activity in CSF is conserved. Comparable results obtained in MS patients with only few small MRI lesions suggest that local chronic inflammatory disease of the central nervous system does not influence prothrombin concentration in the CSF if the blood-CSF barrier function is normal.
尽管凝血酶原是由中枢神经系统内的细胞产生的，但其在脑脊液（CSF）中的存在情况尚未得到研究。我们测定了18名“正常”对照患者和4名复发缓解型多发性硬化症（MS）患者配对样本中脑脊液中凝血酶原的浓度，并参考了血浆中的浓度。新开发的酶联免疫吸附测定（ELISA）具有很高的特异性（与凝血酶无交叉反应）和敏感性（检测限为0.7 ng/ml），批内不精密度CV = 8.3%，批间不精密度CV = 7.0%。正常脑脊液中凝血酶原的平均浓度为0.55 mg/l（CV±33%，范围：0.28 - 0.93 mg/l），正常血浆中为121.8 mg/l±21%，导致脑脊液/血浆浓度平均商（Q(Proth)）为4.5×10⁻³（CV±35%，范围：2.1 - 8.3×10⁻³），与该组受试者的白蛋白平均商Q(Alb) = 5.8×10⁻³相对应。由于Q(Proth)以及凝血酶原的分子量（72 kDa）与白蛋白相似，我们得出结论，正常人脑脊液中的凝血酶原主要（>95%）来源于血液。脑脊液中的酶活性得以保留。在仅有少量小MRI病变的MS患者中获得的类似结果表明，如果血脑屏障功能正常，中枢神经系统的局部慢性炎症疾病不会影响脑脊液中凝血酶原的浓度。
