This Shared Instrumentation Grant is for a confocal microscope and 3-D image analysis work station. This equipment will provide a new technology to advance the research programs of 7 NIH-funded researchers, conducting a total of 9 NIH-funded research projects with strong applications for this technology. The specific projects, and their proposed applications of confocal imaging and 3-D image analysis are as follows: 1) 3-D reconstruction of functionally-identified subgroups of output neurons in the primary gustatory nucleus after intracellular injection of fluorescent dye; 2) visualization and morphometrics of subcellular components (stereocilia and vacuoles) of hair cells exposed to temporary deafness- inducing noise; 3) morphometrics of fluorescent retrogradely-labeled cells innervating the heart in intact sensory and sympathetic ganglia, in chick embryos with cardiac disfunction; 4) imaging of intact cornea to measure volume changes in conjunction with tracking Ca++ movement with fluorescent dyes, to study water and ion transport in corneal epithelium; 5) imaging of subcellular organelles in the cornea of the intact globe using endogenous fluorescence of the mitochondrial redox chain to asses viability of the cornea under varying ambient oxygen concentrations; 6) imaging through intact and opaque corneas to asses potentially deleterious effects of H2O2 concentrations on morphology of the ciliary process, corneal endothelium and lens epithelium; 7) imaging of developing embryonic cardiac outflow tracts to study organization of the structured, 3-D elastic matrix, using fluorescent labeling of matrix components and 8) disruption of this process by neutral crest ablation; and 9) examination of the relationship of the structure of extracellular matrix constituents, to its ability to support nerve regeneration during attempted nerve repair. The investigators are faculty in Anatomy, Physiology and Endocrinology, and Ophthalmology at Medical College of Georgia, and Electrical Engineering at Georgia Institute of Technology. They with the Anatomy chairman, and the departmental confocal support person , will constitute an Executive Committee to oversee use of the facility. Dr. Barry Masters, who has extensive experience in confocal imaging, and Dr. Thomas Rosenquist, who is conducting research at a confocal facility at Univ. of South Carolina, will provide expertise and assistance to the other users and technical support in setting up the facility.