Involvement of GABA(A) Receptors in the Neuroprotective Effect of Theanine on Focal Cerebral Ischemia in Mice

J Pharmacol Sci. 2007 Oct;105(2):211-4. doi: 10.1254/jphs.scz070901. Epub 2007 Oct 6.

Abstract

We investigated the involvement of gamma-aminobutyric acid(A) (GABA(A)) receptors in the neuroprotective effect of gamma-glutamylethylamide (theanine), a component of Japanese green tea, following a 4-h middle cerebral artery (MCA) occlusion in mice. Theanine (1 mg/kg) reduced the size of the cerebral infarct and alterations of NeuN, GFAP, and Iba 1 expression levels at 24 h after MCA occlusion. This neuroprotective effect of theanine was prevented by bicuculline (GABA(A)-receptor antagonist, 10 mg/kg) but not 3-mercaptopropionic acid (glutamate decarboxylase inhibitor). These results suggest that the neuroprotective effect of theanine is mediated, at least in part, by GABA(A) receptors.

MeSH terms

  • Animals
  • Brain Ischemia / drug therapy*
  • Calcium-Binding Proteins / drug effects
  • Calcium-Binding Proteins / metabolism
  • Camellia sinensis / chemistry
  • DNA-Binding Proteins
  • Disease Models, Animal
  • Gene Expression Regulation / drug effects
  • Glial Fibrillary Acidic Protein / drug effects
  • Glial Fibrillary Acidic Protein / metabolism
  • Glutamates / pharmacology*
  • Infarction, Middle Cerebral Artery
  • Male
  • Mice
  • Microfilament Proteins
  • Nerve Tissue Proteins / drug effects
  • Nerve Tissue Proteins / metabolism
  • Neuroprotective Agents / pharmacology*
  • Nuclear Proteins / drug effects
  • Nuclear Proteins / metabolism
  • Receptors, GABA-A / drug effects*
  • Receptors, GABA-A / metabolism
  • Tea / chemistry

Substances

  • Aif1 protein, mouse
  • Calcium-Binding Proteins
  • DNA-Binding Proteins
  • Glial Fibrillary Acidic Protein
  • Glutamates
  • Microfilament Proteins
  • Nerve Tissue Proteins
  • NeuN protein, mouse
  • Neuroprotective Agents
  • Nuclear Proteins
  • Receptors, GABA-A
  • Tea
  • theanine