title: Tetrodotoxin inhibits the formation of refined retinotopography in goldfish.
abstract: One optic nerve of mature goldfish was crushed in the orbit and allowed to regenerate. During regeneration impulse activity was eliminated by periodic intraocular injections of tetrodotoxin (TTX). At 32-104 days, the retinotopography of the retinotectal projection was measured autoradiographically by intraocular [3H]proline injections simultaneous with either small (10-20 degrees sector) or half retinal mapping lesions. TTX had no effect on the time-course and quality of the regeneration of gross topography seen with half retina mapping, but indefinitely inhibited higher order (refined) retinotopography normally seen by 2 months with retina sector mapping.
mesh_terms: D000200:Action Potentials; D000818:Animals; D001931:Brain Mapping; D006054:Goldfish / Q000502:physiology; D009416:Nerve Regeneration / Q000187:drug effects*; D009900:Optic Nerve / Q000187:drug effects / Q000502:physiology*; D020221:Optic Nerve Injuries; D012160:Retina / Q000502:physiology*; D013779:Tetrodotoxin / Q000494:pharmacology*; D014794:Visual Fields
chemical_list: D013779:Tetrodotoxin