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Updated: Jun 21, 2026
Transsynaptic Tracing from Peripheral Targets with Pseudorabies Virus Followed by Cholera Toxin and Biotinylated Dextran Amines Double Labeling
Published on: September 14, 2015
Multiple neuroanatomical tract-tracing using fluorescent Alexa Fluor conjugates of cholera toxin subunit B in rats
William L Conte1, Hiroaki Kamishina, Roger L Reep
1Department of Physiological Sciences, University of Florida, Gainesville, FL, USA. billy.conte@mbi.ufl.edu
Abstract:
Cholera toxin subunit B (CTB) is a highly sensitive retrograde neuroanatomical tracer. With the new availability of fluorescent Alexa Fluor (AF) conjugates of CTB, multiple neuroanatomical connections can be reliably studied and compared in the same animal. Here we provide a protocol that describes the use of AF-CTB for studying connections in the central nervous system of rats. The viscous properties of CTB allow small and discreet injection sites yet still show robust retrograde labeling. Furthermore, the AF conjugates are extremely bright and photostable, compared with other conventional fluorescent tracers. This protocol can also be adapted for use with other neuroanatomical tracers. Including a 7-d survival period, this protocol takes approximately 11 to 12 d to complete in its entirety.
