L-Theanine intake increases threshold for limbic seizures but decreases threshold for generalized seizures

Nutr Neurosci. 2013 Mar;16(2):78-82. doi: 10.1179/1476830512Y.0000000033. Epub 2012 Dec 4.


L-Theanine, an ethylamide derivate of glutamate found in abundance in green tea, has been shown to exert beneficial actions in animal models for several neurological disorders. We here investigated for the first time the effect of L-theanine intake on seizure susceptibility using acute pilocarpine and pentylenetetrazol (PTZ) mouse models for studying, respectively, limbic seizures or primarily generalized seizures. Moreover, we studied the effect of l-theanine intake on extracellular hippocampal and cortical glutamate and gamma-aminobutyric acid (GABA) levels, using in vivo microdialysis. Feeding mice with a 4% L-theanine solution significantly decreased their susceptibility to pilocarpine-induced seizures whereas susceptibility to PTZ-induced seizures was increased. The latter effect was linked to decreased extracellular GABA concentrations in frontal cortex.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Disease Models, Animal
  • GABA Agents / metabolism
  • Glutamates / administration & dosage
  • Glutamates / pharmacology*
  • Glutamic Acid / metabolism
  • Hippocampus / drug effects
  • Hippocampus / metabolism
  • Male
  • Mice
  • Mice, Inbred Strains
  • Microdialysis
  • Pentylenetetrazole / adverse effects
  • Pilocarpine / adverse effects
  • Seizures / chemically induced
  • Seizures / drug therapy*
  • Tea / chemistry
  • gamma-Aminobutyric Acid / metabolism*


  • GABA Agents
  • Glutamates
  • Tea
  • Pilocarpine
  • Glutamic Acid
  • gamma-Aminobutyric Acid
  • theanine
  • Pentylenetetrazole