Biological model for the in vivo measurement of rate of serotonin synthesis in the brain

  • M. Diksic
  • S. Nagahiro
  • T. L. Sourkes
Part of the Journal of Neural Transmission book series (NEURAL SUPPL, volume 29)


A biological model for the measurement of the rate of serotonin synthesis in rat brain with α-[14C]methyl-L-tryptophan is described. The rate of serotonin synthesis in several grossly dissected brain structures is reported. The half-life of the precursor pool, estimated from kinetic data, is between 20 and 25 min. The method allows, for the first time, measurement of the brain serotonin synthesis rate without any pharmacological manipulation and does not require separation of metabolites. Autoradiographic data are also presented to demonstrate anatomical resolution of this method. The synthesis rate can be estimated in a large number of discrete structures when autoradiography is applied. Long retention of the tracer in brain is also demonstrated.


Biological Model Dorsal Raphe Nucleus Cereb Blood Flow Pharmacological Manipulation Serotonin Synthesis 
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Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • M. Diksic
    • 1
    • 3
  • S. Nagahiro
    • 1
  • T. L. Sourkes
    • 2
  1. 1.Montreal Neurological Institute and Hospital, and Department of Neurology and NeurosurgeryMcGill UniversityMontrealCanada
  2. 2.Departments of Psychiatry and BiochemistryMcGill UniversityMontrealCanada
  3. 3.Medical Cyclotron UnitMcGill UniversityMontrealCanada

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