Blanchard Nadège, Richert Lysiane, Notter Brigitte, Delobel Frederic, David Pascale, Coassolo Philippe, Lavé Thierry
Pharma Research Basel (70/131), F. Hoffmann-LaRoche Ltd., Pharmaceuticals Division, Grenzacherstrasse No. 124, CH 4070 Basel, Switzerland.
Eur J Pharm Sci. 2004 Oct;23(2):189-99. doi: 10.1016/j.ejps.2004.07.007.
The objective of the present study was to compare two configurations of the hepatocyte model namely suspensions (SH) and conventional primary cultures (CPC) for their ability to predict the hepatic clearance in vivo in the rat and, to investigate the impact of serum on the prediction accuracy. The metabolic competences of several cytochrome P450 isoenzymes were investigated both in CPC and SH in the presence or absence of serum. Under the same conditions, the in vitro intrinsic clearance of six test compounds metabolised by a variety of phase I and phase II enzymes (antipyrine, RO-X, mibefradil, midazolam, naloxone and oxazepam) were derived from Vmax/Km scaled up to the corresponding in vivo hepatic metabolic clearance. CYP activities were shown to be stable in both CPC and SH for up to 6 h of incubation, except for the CYP 3A1 activity that decreased in CPC even in the presence of serum. Moreover, the clearances predicted from SH in the presence of serum were closer to the in vivo values than those obtained from CPC. SH represent a convenient model to assess the hepatic metabolism of xenobiotics, the presence of serum in the incubation medium significantly improved in several instances the quality of the predictions.
本研究的目的是比较肝细胞模型的两种配置，即悬浮液（SH）和传统原代培养物（CPC）预测大鼠体内肝脏清除率的能力，并研究血清对预测准确性的影响。在有或无血清存在的情况下，研究了CPC和SH中几种细胞色素P450同工酶的代谢能力。在相同条件下，由多种I相和II相酶（安替比林、RO-X、米贝拉地尔、咪达唑仑、纳洛酮和奥沙西泮）代谢的六种受试化合物的体外内在清除率由Vmax/Km推导得出，并按比例放大至相应的体内肝脏代谢清除率。结果显示，在长达6小时的孵育过程中，CPC和SH中的CYP活性均保持稳定，但CPC中的CYP 3A1活性即使在有血清存在的情况下也会下降。此外，血清存在时SH预测的清除率比CPC得到的清除率更接近体内值。SH是评估外源化合物肝脏代谢的便捷模型，孵育培养基中血清的存在在多个实例中显著提高了预测质量。
