Transmembrane Ion Channel (IMAGE) University of Pennsylvania School of Medicine Caption Graphic representation of a potassium transmembrane ion channel. Credit Toshinori Hoshi, Ph.D., Perelman School of Medicine, University of Pennsylvania 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.