Distribution of Endothelin—Converting Enzyme in the Heart of Human and Rat

Objective -To determine the distribution of endothelin-converting enzyme (ECE) in different parts of the heart of adult normal Chinese and Sprague-Dawley (SD-) rat. Methods-The ECE mRNA was determined by semi-quantitative reverse transcription-polymer ase chain reaction. ECE activity was determined by the conversion of exogenously added big endothelin-1 to endothelin-1. Results : The ECE mRNA and activity were detected in different parts of the heart. In human, the ECE expression in atria was significantly higher than those in ventricles. No significant difference was observed between left and right atrium, and among the left ventricle, right ventricle and interventricular septum. The distribution of ECE activity was consistent with that of mRNA expression. The rat had a similar pattern of distribution of either ECE mRNA expression or activity with that of human. Conclusion :ECE exists in all parts of the heart of normal Chinese and SD rat and its distribution is similar in human and rat hearts.