Martin J. Lohse, M.D. born 26 August 1956, is a German physician and pharmacologist doing research on G protein-coupled receptors. Since 1993, he is a Professor of Pharmacology at the University of Würzburg, Germany, as well as Chairman of the Rudolf Virchow Center (since 2001). He received his exam in medicine as well as his M.D. from the University of Göttingen, and did research in pharmacology at the University of Heidelberg, Duke University and the GeneCenter in Munich. His research focusses on the role of receptors in heart failure and on the mechanisms of their activation and inactivation. While working with Robert Lefkowitz at Duke University he discovered beta-arrestins, proteins that regulate the function of certain cell surface receptors. He discovered that beta-1 adrenergic receptors and their regulatory G protein-coupled receptor kinases are dysregulated in heart failure. The observation that increased β1-adrenergic receptor levels and signaling cause long-term cardiac damage contributed to the use of beta-blockers in heart failure patients. Further studies by his lab showed that heart failure is accompanied by a specific type of activation of so-called ERK protein kinases (Extracellular signal-regulated kinases). Another regulatory protein, Raf kinase inhibitor protein (RKIP), was shown to exert beneficial effects on cardiac structure and function. Lohse pioneered the use of optical techniques to determine, where and how fast receptors become activated by hormones and neurotransmitters.