Bailey D N
Department of Pathology, University of California Medical Center, San Diego 92103-8320, USA.
J Anal Toxicol. 1998 Sep;22(5):355-8. doi: 10.1093/jat/22.5.355.
The binding of cocaine (COC) and cocaethylene (CE) to whole human liver homogenates in vitro was studied by equilibrium dialysis. Drugs were measured by high-pressure liquid chromatography. Up to 32% of COC and up to 43% of CE were bound. Scatchard analysis suggested a high-affinity, low-capacity binder for both COC (Ka, 4.69 x 10(4) L/mol; Bo, 1.08 x 10(-5) mol/L) and CE (Ka, 4.38 x 10(4) L/mol; Bo, 1.54 x 10(-5) mol/L). In addition, low-affinity, high-capacity binders for COC (Ka, 2.93 x 10(3) L/mol; Bo, 1.32 x 10(-4) mol/L) and CE (Ka, 6.50 x 10(3) L/mol; Bo, 1.11 x 10(-4) mol/L) were noted. Finally, for both compounds, very low-affinity, high-capacity binding, which was likely nonspecific in nature, was defined as follows: COC, Ka, 8.00 x 10(2) L/mol; Bo, 5.45 x 10(-4) mol/L and CE, Ka, 2.10 x 10(3) L/mol; Bo, 3.71 x 10(-4) mol/L. The binding profiles of COC and CE in liver were compared with those in human serum and placenta studied previously by this laboratory.
采用平衡透析法研究了可卡因(COC)和可口卡因(CE)在体外与全人类肝脏匀浆的结合情况。通过高压液相色谱法测定药物含量。结果显示,高达32%的COC和高达43%的CE会发生结合。Scatchard分析表明,COC(Ka,4.69×10⁴L/mol;Bo,1.08×10⁻⁵mol/L)和CE(Ka,4.38×10⁴L/mol;Bo,1.54×10⁻⁵mol/L)均有高亲和力、低容量的结合物。此外,还发现了COC(Ka,2.93×10³L/mol;Bo,1.32×10⁻⁴mol/L)和CE(Ka,6.50×10³L/mol;Bo,1.11×10⁻⁴mol/L)的低亲和力、高容量结合物。最后,对于这两种化合物,定义了亲和力极低、容量高的结合情况,其可能本质上是非特异性的:COC,Ka,8.00×10²L/mol;Bo,5.45×10⁻⁴mol/L;CE,Ka,2.10×10³L/mol;Bo,3.71×10⁻⁴mol/L。本实验室将肝脏中COC和CE的结合情况与之前研究的人血清和胎盘中的结合情况进行了比较。