1-(3-sulfonatopropyl)-4-(beta)(2-(di-n-butylamino)-6-naphthylvinyl)pyridinium-betaine and 2-3-dioxo-6-nitro-7-sulfamoylbenzo(f)quinoxaline

Optical recording of neuronal activities using voltage-sensitive dyes (VSDs) is a useful method for simultaneous multi-site recording. However, it has been rather difficult to distinguish optical signals from individual, identified cells. We applied the optical recording technique using a high-speed charge coupled device (CCD) imaging system to a teleost thalamic nucleus, corpus glomerulosum (CG) which has a well-defined histological organization and large postsynaptic dendrites. Patch-like dye (di-4-ANEPPS) signals were observed in the dendritic layer of the CG in response to afferent nerve stimulations. These responses were completely blocked by an alpha-amino-3-hydroxy-5-methyl-4-isoxazole-proprionate (AMPA) receptor antagonist, did not propagate, and the size of the patches were close to that of a single dendritic tip of the 'large cell'. Thus, we found that these patch-like VSD signals most likely represent postsynaptic potentials at individual dendritic tips of the large cells.

Topics: Animals; Dendrites; Electronic Data Processing; Excitatory Amino Acid Antagonists; Fishes; Fluorescent Dyes; Image Processing, Computer-Assisted; Membrane Potentials; Pyridinium Compounds; Quinoxalines; Receptors, AMPA; Synaptic Membranes; Thalamus