Vigushin D M, Pepys M B, Hawkins P N
Department of Medicine, Royal Postgraduate Medical School, Hammersmith Hospital, London, United Kingdom.
J Clin Invest. 1993 Apr;91(4):1351-7. doi: 10.1172/JCI116336.
Plasma and whole-body turnover studies of human C-reactive protein (CRP), isolated from a single normal healthy donor and labeled with 125I, were undertaken in 8 healthy control subjects and 35 hospitalized patients including cases of rheumatoid arthritis, systemic lupus erythematosus, infections, and neoplasia. Plasma clearance of 125I-CRP closely approximated to a monoexponential function and was similar in the control and all patient groups. There was no evidence for accelerated clearance or catabolism of CRP in any of the diseases studied. The 19-h half-life was more rapid than that of most human plasma proteins studied previously, and the fractional catabolic rate was independent of the plasma CRP concentration. The synthesis rate of CRP is thus the only significant determinant of its plasma level, confirming the validity of serum CRP measurement as an objective index of disease activity in disorders associated with an acute-phase response. Approximately 90% of injected radioactivity was recovered in the urine after 7 d, and scintigraphic imaging studies with 123I-labeled CRP in 10 patients with different focal pathology showed no significant localization of tracer. The functions of CRP are thus likely to be effected predominantly in the fluid phase rather than by major deposition at sites of tissue damage or inflammation.
对从一名正常健康供体分离并标记有¹²⁵I的人C反应蛋白（CRP）进行了血浆和全身周转率研究，研究对象包括8名健康对照者和35名住院患者，后者包括类风湿性关节炎、系统性红斑狼疮、感染和肿瘤患者。¹²⁵I-CRP的血浆清除率非常接近单指数函数，在对照组和所有患者组中相似。在所研究的任何疾病中，均未发现CRP清除或分解代谢加速的证据。19小时的半衰期比之前研究的大多数人血浆蛋白的半衰期都要短，而且分解代谢分数率与血浆CRP浓度无关。因此，CRP的合成率是其血浆水平的唯一重要决定因素，这证实了血清CRP测量作为与急性期反应相关疾病中疾病活动客观指标的有效性。7天后，约90%的注入放射性在尿液中回收，对10名患有不同局灶性病变的患者进行的¹²³I标记CRP闪烁成像研究显示，示踪剂没有明显的定位。因此，CRP的功能可能主要在液相中发挥作用，而不是主要沉积在组织损伤或炎症部位。
