This proposal requests funds for the acquisition of fluorescence digital imaging hardware that will be interfaced to an existing video-enhanced DIC microscopy system. The requested instrumentation will allow real-time fluorescence ratio imaging, rapid sequential DIC and fluorescence imaging, and rapid sequential imaging, of FITC and texas red fluorophores. Proposed investigations which will utilized fluorescence imaging techniques address fundamental cell physiological problems such as the mechanisms and control of vasopressin-induced apical membrane water channel insertion and retrieval in "tight" epithelial cells, the role of Ca2+ in regulating renal glomerular mesangial cell contractile behavior and in controlling epithelial cell volume maintenance pathways and transcellular cross-talk mechanisms, receptor-hormone complex cycling in mesangial cells, and the role of capillary endothelial cells and intercellular communication in regulating mesangial cell contractile properties. Fluorescence imaging techniques provide an important new experimental tool for ongoing funded investigations in the laboratories of the P.I. and co-investigators.
