Drs. Zigman and Mani (IMAGE) UT Southwestern Medical Center Caption Dr. Jeffrey Zigman, left, and Dr. Bharath Mani led a UT Southwestern study that found a signaling molecule regulates release of the hunger hormone ghrelin. Credit UT Southwestern Medical Center Usage Restrictions With credit line License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.