A MACRO IMAGE-ANALYSIS OF FURA-2 FLUORESCENCE TO VISUALIZE THE DISTRIBUTION OF FUNCTIONAL GLUTAMATE RECEPTOR SUBTYPES IN HIPPOCAMPAL SLICES

The distribution of functional glutamate receptor subtypes was visualized as regional changes in intracellular Ca2+ concentration induced by administration of a specific agonist for each subtype. An image of the fura-2 fluorescence from a whole hippocampal slice was directly excited at 340 or 380 nm through an optical fibre and observed via a low-magnification objective lens (X 4). A heterogeneous distribution of N-methyl-D-aspartate (NMDA) and non-NMDA subtypes was demonstrated by the ratio of fluorescence intensities before and after administration of each agonist. This 'macro' image analysis can reveal distributions of multiple functional receptors in a living brain slice.