Validation of the biological responses of reference drugs in the zebrafish embryo by electrocardiographic analysis and by novel phenotyping tools

Drug toxicities represent a major problem in drug discovery and development; therefore there is a push to develop new technologies to detect these early on. In this thesis I investigated the utility of zebrafish embryos and larvae in evaluating the biological activity of novel compounds and developed new methods for assaying the potential toxic effects of drugs \(in\) \(vivo\). An electrocardiogram (ECG) recording set-up for zebrafish embryos and larvae was developed to assay drug-induced cardiotoxicity. The set-up was validated by testing drugs known to induce cardiotoxicity in humans in zebrafish larvae. The results obtained were in agreement with those documented in humans demonstrating the utility of the zebrafish larva in detecting drug-induced cardiotoxicity. The zebrafish embryo was also found to be a useful model for probing the biological activity of novel and marketed compounds providing an insight into the relationship between chemical properties and biological effects. Additionally, the assessment of the anti-inflammatory activity of a set of reference drugs revealed that the zebrafish larva also presents a promising model for therapeutic drug screens. Overall, the results described in this thesis show that the zebrafish presents an effective, reliable and rapid model for assessing the biological activity of drugs \(in\) \(vivo\)