Bussek Alexandra, Schmidt Matthias, Bauriedl Jessica, Ravens Ursula, Wettwer Erich, Lohmann Horst
Lohmann Research Equipment, Am Förderturm 9, D-44575 Castrop-Rauxel, Germany.
J Pharmacol Toxicol Methods. 2012 Sep;66(2):145-51. doi: 10.1016/j.vascn.2011.12.002. Epub 2011 Dec 30.
We have recently introduced the use of mammalian cardiac tissue slices for in vitro drug testing purposes. Here we show how this method can be applied for long-term studies in safety pharmacology.
In freshly prepared cardiac slices from guinea-pig or rat ventricle, extracellular field potentials (FP) and intracellular action potentials (AP) were recorded in response to electrical stimulation using the 4-channel heart slice screening system 'Synchroslice'. To assess viability of the slices on consecutive days after preparation, drug effects on FP/AP parameters, like duration and latency, were monitored.
In the presence of the potassium channel blocker E4031 (1 μM), FP and AP duration (FPD and APD) were significantly increased (FPD, 39.0%; APD, 28.1%) in guinea-pig ventricular slices. Similar changes were observed 24-28 h after slice preparation (FPD, 48.6%; APD, 25.4%). Furthermore, AP duration was reduced in the presence of the calcium channel blocker nifedipine (10 μM) on the day of preparation (40.5%) and 24-28 h later (38.7%). In contrast, in the presence of the potassium channel blocker 4-aminopyridine (30 mM) AP duration was prolonged 4.95 and 4.19-fold, 2-8 h and 24-28 h after preparation, respectively. Finally, FP propagation was repeatedly slowed down by the gap junction blocker carbenoxolone (30 μM), as revealed from FP onset latency increases observed on three consecutive days (2-8 h after preparation, 93.0%; 24-28 h, 76.8%, 48-56 h, 61.7%).
Freshly isolated cardiac slices reproduced established physiological and pharmacological responses for more than 24 h after preparation. Thus, cardiac slices can be used for several days after preparation which makes them a robust model for electrophysiological studies. We propose that cardiac slices can become a versatile tool in heart research and risk assessment of drugs.
我们最近引入了使用哺乳动物心脏组织切片进行体外药物测试的方法。在此，我们展示了该方法如何应用于安全药理学的长期研究。
在豚鼠或大鼠心室新鲜制备的心脏切片中，使用四通道心脏切片筛选系统“同步切片”记录细胞外场电位（FP）和细胞内动作电位（AP）对电刺激的反应。为了评估切片制备后连续几天的活力，监测药物对FP/AP参数（如持续时间和潜伏期）的影响。
在存在钾通道阻滞剂E4031（1μM）的情况下，豚鼠心室切片中的FP和AP持续时间（FPD和APD）显著增加（FPD，39.0%；APD，28.1%）。在切片制备后24 - 28小时观察到类似变化（FPD，48.6%；APD，25.4%）。此外，在制备当天（40.5%）和24 - 28小时后（38.7%），在存在钙通道阻滞剂硝苯地平（10μM）的情况下，AP持续时间缩短。相反，在存在钾通道阻滞剂4 - 氨基吡啶（30 mM）的情况下，AP持续时间在制备后2 - 8小时和24 - 28小时分别延长了4.95倍和4.19倍。最后，缝隙连接阻滞剂羧苄青霉素（30μM）反复减慢FP传播，这从连续三天观察到的FP起始潜伏期增加中得以揭示（制备后2 - 8小时，93.0%；24 - 28小时，76.8%，48 - 56小时，61.7%）。
新鲜分离的心脏切片在制备后24小时以上再现了既定的生理和药理反应。因此，心脏切片在制备后可使用数天，这使其成为电生理研究的可靠模型。我们提出心脏切片可成为心脏研究和药物风险评估中的一种通用工具。
