Agarwal R P, McPherson R A, Threatte G A
Ther Drug Monit. 1985;7(1):61-5. doi: 10.1097/00007691-198503000-00010.
Measurement of whole blood and plasma levels of cyclosporin A (CsA) by radioimmunoassay in kidney transplant recipients receiving the drug showed that CsA concentrations in plasma increased nonlinearly when whole blood levels of the drug exceeded 1,000 ng/ml. At low plasma levels (less than 200 ng/ml), most of the CsA in the blood was in the nonplasma component, indicating that cellular elements have high affinity for CsA. Comparison of nonplasma CsA concentrations in two patients with hematocrit values of 32.5 and 35% showed that in the patient with a hematocrit of 35% the cellular associated drug was twice as great as that in the other patient, indicating that there may be significant differences in the cellular affinity of CsA in patients with similar hematocrits. Linear regression analysis of the cellular associated CsA versus plasma levels of the drug in a double-reciprocal plot showed a drug saturation capacity of 6,060 ng/ml in the nonplasma component of blood in the patient with a hematocrit of 35%. Similar analyses in the other patients indicated saturation capacities ranging from 4,750 to 10,400 ng/ml.
通过放射免疫分析法对接受环孢素A（CsA）治疗的肾移植受者的全血和血浆中环孢素A水平进行测量，结果显示，当全血中环孢素A水平超过1000 ng/ml时，血浆中环孢素A浓度呈非线性增加。在低血浆水平（低于200 ng/ml）时，血液中的大部分环孢素A存在于非血浆成分中，这表明细胞成分对环孢素A具有高亲和力。对两名血细胞比容值分别为32.5%和35%的患者的非血浆环孢素A浓度进行比较，结果显示血细胞比容为35%的患者中与细胞相关的药物是另一名患者的两倍，这表明血细胞比容相似的患者中环孢素A的细胞亲和力可能存在显著差异。在双倒数图中对血细胞比容为35%的患者血液非血浆成分中与细胞相关的环孢素A与药物血浆水平进行线性回归分析，结果显示药物饱和容量为6060 ng/ml。对其他患者进行的类似分析表明，饱和容量范围为4750至10400 ng/ml。
