Title:Neurotransmitters, Psychotropic Drugs and Microglia: Clinical Implications for Psychiatry
Volume: 20
Issue: 3
Author(s): T. A. Kato, Y. Yamauchi, H. Horikawa, A. Monji, Y. Mizoguchi, Y. Seki, K. Hayakawa, H. Utsumi and S. Kanba
Affiliation:
Keywords:
Microglia, antipsychotics, antidepressants, antiepileptics, minocycline, BDNF, dopamine, serotonin, norepinephrine,
schizophrenia, depression, epilepsy, psychiatry
Abstract: Psychiatric disorders have long and dominantly been regarded to be induced by disturbances of neuronal networks including
synapses and neurotransmitters. Thus, the effects of psychotropic drugs such as antipsychotics and antidepressants have been understood
to modulate synaptic regulation via receptors and transporters of neurotransmitters such as dopamine and serotonin. Recently, microglia,
immunological/inflammatory cells in the brain, have been indicated to have positive links to psychiatric disorders. Positron emission tomography
(PET) imaging and postmortem studies have revealed microglial activation in the brain of neuropsychiatric disorders such as
schizophrenia, depression and autism. Animal models of neuropsychiatric disorders have revealed the underlying microglial pathologies.
In addition, various psychotropic drugs have been suggested to have direct effects on microglia. Until now, the relationship between microglia,
neurotransmitters and psychiatric disorders has not been well understood. Therefore, in this review, at first, we summarize recent
findings of interaction between microglia and neurotransmitters such as dopamine, serotonin, norepinephrine, acetylcholine and glutamate.
Next, we introduce up-to-date knowledge of the effects of psychotropic drugs such as antipsychotics, antidepressants and antiepileptics
on microglial modulation. Finally, we propose the possibility that modulating microglia may be a key target in the treatment of
various psychiatric disorders. Further investigations and clinical trials should be conducted to clarify this perspective, using animal in
vivo studies and imaging studies with human subjects.