背景:啮齿动物模型通常用于评估药物的安全性和发育毒性,以及对其分布的分析。这些模型需要牺牲父母的女性,在估计胚胎数量和发育阶段方面有挑战,而且昂贵且耗时。在这项研究中,我们使用受精卵作为替代模型来解决两种抗癫痫药物在发育中的大脑中的药物分布问题,丙戊酸(VPA)和拉莫三嗪(LTG)处于两个发育阶段。
方法:在胚胎第13天(E13)或E16天将VPA或LTG注射到卵的尿囊中。在5分钟至24小时的时间点收获整个鸡脑,并使用GC/MS和LC-MS/MS确定药物的浓度。对于VPA和LTG,分别。
结果:VPA和LTG具有不同的吸收和消除阶段,早在注射后5-15分钟就在大脑中发现。两种药物都以临床相关浓度到达大脑,Cmax为计算浓度的10-30%,假设整个鸡蛋均匀分布。与E16相比,当在E13注射时,LTG浓度更高。
结论:鸡胚模型可能是临床前药物分布研究的合适替代动物模型。它可以轻松地在个体水平上进行产前发育,有精确数量的实验动物,重现性高,时间和成本低。了解使用不同药物在不同发育阶段到达大脑的浓度对于规划和解释神经发育毒性研究很重要。
BACKGROUND: Rodent models are routinely used to assess the safety and developmental toxicity of pharmaceuticals, along with analysis of their distribution. These models require sacrifice of parent females, have challenges in the estimation of the number of embryos and stage of development, and are expensive and time-consuming. In this
study, we used fertilized chicken eggs as an alternative model to address drug distribution to the developing brain of two antiepileptic drugs, valproic acid (VPA) and lamotrigine (LTG) at two developmental stages.
METHODS: VPA or LTG was injected into the allantois of the egg on embryonic day 13 (E13) or E16. Whole chicken brains were harvested at time-points of 5 min to 24 h and the concentrations of the drugs determined using GC/MS and LC-MS/MS, for VPA and LTG, respectively.
RESULTS: VPA and LTG had distinct absorption and elimination phases and were found in the brain as early as 5-15 min after injection. Both drugs reached the brain in clinically relevant concentrations, with Cmax 10-30% of the calculated concentration assuming uniform distribution throughout the egg. LTG concentrations were higher when injected at E13 compared to E16.
CONCLUSIONS: The chicken embryo model may be a suitable alternative animal model for preclinical drug distribution studies. It enables to easily approach antenatal development on an individual level, with a precise number of experimental animals, high reproducibility and low time and cost. Knowledge of the concentrations reaching the brain at different developmental stages with different drugs is important for the planning and interpretation of neurodevelopmental toxicity studies.