The halogenated tetrahydro-β-carboline “TaClo”: A progressively-acting neurotoxin

  • Christine Heim
  • K.-H. Sontag
Part of the Journal of Neural Transmission. Supplementa book series (NEURAL SUPPL, volume 50)


“TaClo”, (1-trichloromethyl-1,2,3,4-tetrahydro-β-carboline) which is structurally very similar to MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyri-dine), increases the sensitivity to apomorphine in aging rats after subchronic daily application (0.2 mg/kg i.p.) for 7 weeks. Nine weeks after the last treatment with TaClo, the running speed of the animals during spontaneous nocturnal activity was significantly diminished, and 9 months after the last injection rats developed a pronounced hypersensitivity to apomorphine (0.4 mg/kg s.c). TaClo, which can be readily produced from endogenous tryptamine and the non-natural aldehyde chloral, appears to be a drug that is able to induce a slowly-developing neurodegenerative process.


Chloral Hydrate Injection Period Postsynaptic Dopamine Receptor Minute Observation Period Striatal Dopaminergic System 
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Copyright information

© Springer-Verlag Wien 1997

Authors and Affiliations

  • Christine Heim
    • 1
  • K.-H. Sontag
    • 1
  1. 1.Department of PsychiatryUniversity of GöttingenGöttingenGermany

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