Porreca (IMAGE) University of Arizona Health Sciences Caption Frank Porreca, MD, associate head, Department of Pharmacology, University of Arizona College of Medicine - Tucson Credit (Photos: The University of Arizona Health Sciences, Noelle Haro-Gomez) Usage Restrictions None 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.