Studies in this laboratory are directed at understanding the molecular mechanisms involved in vascular smooth muscle contraction and relaxation. To this end, the lab has developed computer-based image analysis techniques to directly study microvessel reactivity under physiological conditions in vitro. Both pharmacological and biochemical tools have also been devised, including fluorescent techniques allowing real-time measurements of intracellular Ca2+ concentration ([Ca2+]i), electrophoresis and western blotting methods for separation and measurement of contractile protein isoforms, and membrane-permeabilization techniques for studying modulation of contractile protein function. The lab is specifically interested in the actions of volatile anesthetic agents which, as studies from this lab indicate, produce endothelium-independent vascular smooth muscle relaxation which is unrelated to changes in either ([Ca2+]i), or myosin phosphorylation. Ongoing studies are directed at elucidating the biochemical basis and physiological importance of this unique mechanism. Another active interest concerns the vascular effects of acute and chronic inflammation, particularly the microvascular changes that occur in septic shock. Utilizing genetically altered NOS2 (or iNOS) knock-out mice, recent studies from this lab indicate that induction of NOS2 gene expression in vascular smooth muscle plays a pivotal role in the development of catecholamine-resistant vasodilation following inflammatory or septic stimuli. Ongoing studies are directed at determining the effects of NOS2-derived nitric oxide on microvessel reactivity, endothelial function, and vascular permeability, and the mechanisms involved.