Electrocardiographic studies of developing rodents exposed in utero to trypan blue.

Techniques, based on computer-assisted analyses of ensembled ECG waveforms, have been developed in this laboratory to serve as a screening procedure for potentially cardiotoxic substances. This procedure was tested on fetal and neonatal rats exposed in utero to two levels of trypan blue, a known cardiovascular teratogen. The offspring of the treated animals exhibited decreased viability, as well as significant levels of both cardiac and noncardiac malformations. Qualitative assessment of ECG irregularities demonstrated an increased number of abnormalities in the treated groups. Correlations were also obtained between observed morphological defects and ECG irregularities in the trypan blue treated groups.