MOLECULAR PHARMACOLOGY OF INHALED ANESTHETICS
The inhaled anesthetics are considered one of the most important medical advances of all time, are used in over 100 million patients every year, and yet remain the most toxic and poorly understood of all drugs. The goal of my laboratory is a translational understanding of inhaled anesthetic pharmacology. Most of the current work is focused on the biophysics of anesthetic/macromolecular interactions because of the importance of establishing a foundation of knowledge at this most basic level, on which the subsequent superstructure of molecular, cellular and organism understanding will be built. We have developed a wide variety of experimental approaches to study inhaled anesthetics binding to proteins, and the structural and dynamic consequences. Thus, photoaffinity labeling, fluorescence spectroscopy, amide hydrogen exchange, low-affinity elution chromatography and differential/isothermal calorimetry have all been introduced and validated for this purpose. Many protein and peptide models are used, including serum albumin and its domains, odorant binding protein, rhodopsin and other G-protein-coupled receptors, ferritin, and de novo designed helical bundles. Our group also uses NMR spectroscopy, x-ray crystallography and molecular dynamic simulations via close collaborations to gain a detailed atomic-level appreciation for the interactions and consequences in both time and space. In collaboration with Pat Loll of Drexel University, we have completed high resolution characterization of halothane, isoflurane and propofol binding sites in apoferritin - the highest affinity inhaled anesthetic binding protein yet described (see Figures 1 & 2). This has yielded considerable insight into the features underlying anesthetic binding, and provided a template for anesthetic discovery. In turn, discovered reagents are providing for novel anesthetic targets discovery. Proteomic and genomic approaches have permitted initial forays into cell and organism implications of our binding results. Wide collaborations with many other departments and institutions have facilitated a rapid, multidisciplinary attack on some of the most fundamental questions in anesthetic pharmacology.