The neuropharmacology of L-theanine(N-ethyl-L-glutamine): a possible neuroprotective and cognitive enhancing agent.
L-theanine (N-ethyl-L-glutamine) or theanine is a major amino acid uniquely found in green tea. L-theanine has been historically reported as a relaxing agent, prompting scientific research on its pharmacology. Animal neurochemistry studies suggest that L-theanine increases brain serotonin, dopamine, GABA levels and has micromolar affinities for AMPA, Kainate and NMDA receptors. In addition has been shown to exert neuroprotective effects in animal models possibly through its antagonistic effects on group 1 metabotrophic glutamate receptors. Behavioural studies in animals suggest improvement in learning and memory. Overall, L-theanine displays a neuropharmacology suggestive of a possible neuroprotective and cognitive enhancing agent and warrants further investigation in animals and humans.
Nathan
Pradeep J
PJ
Behavioural Neuroscience Laboratory, Department of Physiology, Monash Center for Brain and Behaviour, Monash University, Australia. Nathan@med.monash.edu.au
Lu
Kristy
K
Gray
M
M
Oliver
C
C
D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D004298:Dopamine / Q000096:biosynthesis; D005971:Glutamates / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D009480:Neuropharmacology; D018696:Neuroprotective Agents / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D018697:Nootropic Agents / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D008517:Phytotherapy; D012701:Serotonin / Q000096:biosynthesis; D013662:Tea; D005680:gamma-Aminobutyric Acid / Q000096:biosynthesis
D005971:Glutamates; D018696:Neuroprotective Agents; D018697:Nootropic Agents; D013662:Tea; D012701:Serotonin; D005680:gamma-Aminobutyric Acid; C026166:theanine; D004298:Dopamine