High resolution imaging of receptor binding in analyzing neuropsychiatric diseases

A method for analyzing high resolution imaging of receptor binding activity in human post-mortem brain specimens is described. The autoradiography technique employed is based on methods previously described by others in which coverslips dipped in tritium-sensitive nuclear track emulsion are placed over a tissue section that has been incubated in a medium containing radioactively-tagged ligand. With this approach, there is a 370-fold increase in resolution from approximately 120 microns available with tritium-sensitive films to 0.33 micron attainable with the emulsion approach. Since the coverslip autoradiogram remains superimposed on the tissue section, individual grains can be routinely quantitated in specific cell types and discrete subregions of the neuropil with the aid of a user-interactive image processing system. Overall, the improved resolution that this approach provides makes it possible to determine whether a particular neuronal sub-type may be preferentially altered by disease processes affecting the brain.