Two-photon imaging of calcium signals within one glomerulus in vivo
Two-photon imaging of receptor neuron input within one glomerulus using calcium imaging. On the left is a two-photon image of a single glomerulus labelled by loading receptor neurons with calcium-sensitive dye and imaged in vivo. On the right is a pseudocolor map of the presynaptic calcium signals evoked by the odorant 2-hexanone. Signals are confined to the glomerulus and are distributed heterogeneously in multiple 'hot-spots' throughout the glomerulus. The hot spots reflect areas of high-density presynaptic terminals.