Multiple neuroanatomical tract-tracing using fluorescent Alexa Fluor conjugates of cholera toxin subunit B in rats

Nat Protoc. 2009;4(8):1157-66. doi: 10.1038/nprot.2009.93. Epub 2009 Jul 16.

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.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Brain / surgery
  • Central Nervous System / anatomy & histology
  • Central Nervous System / physiology
  • Cholera Toxin / analysis*
  • Craniotomy / methods
  • Fluorescent Dyes / analysis*
  • Histocytological Preparation Techniques*
  • Organic Chemicals / analysis
  • Rats

Substances

  • Alexa594
  • Fluorescent Dyes
  • Organic Chemicals
  • Cholera Toxin