Enhancement of GABAergic activity: neuropharmacological effects of benzodiazepines and therapeutic use in anesthesiology.
GABA is the major inhibitory neurotransmitter in the central nervous system (CNS). The type A GABA receptor (GABA(A)R) system is the primary pharmacological target for many drugs used in clinical anesthesia. The α1, β2, and γ2 subunit-containing GABA(A)Rs located in the various parts of CNS are thought to be involved in versatile effects caused by inhaled anesthetics and classic benzodiazepines (BZD), both of which are widely used in clinical anesthesiology. During the past decade, the emergence of tonic inhibitory conductance in extrasynaptic GABA(A)Rs has coincided with evidence showing that these receptors are highly sensitive to the sedatives and hypnotics used in anesthesia. Anesthetic enhancement of tonic GABAergic inhibition seems to be preferentially increased in regions shown to be important in controlling memory, awareness, and sleep. This review focuses on the physiology of the GABA(A)Rs and the pharmacological properties of clinically used BZDs. Although classic BZDs are widely used in anesthesiological practice, there is a constant need for new drugs with more favorable pharmacokinetic and pharmacodynamic effects and fewer side effects. New hypnotics are currently developed, and promising results for one of these, the GABA(A)R agonist remimazolam, have recently been published.
Department of Anesthesiology, Intensive Care, Emergency Care and Pain Medicine, Turku University Hospital, P.O. Box 52 (Kiinamyllynkatu 4-8), FI-20520 Turku, Finland. teijo.saari@gmail.com
Teijo I
TI
Saari
Mikko
M
Uusi-Oukari
Jouni
J
Ahonen
Klaus T
KT
Olkkola
D018686:Anesthetics, Intravenous / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000627:therapeutic use; D000818:Animals; D014151:Anti-Anxiety Agents / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology / Q000627:therapeutic use; D001569:Benzodiazepines / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000627:therapeutic use; D002490:Central Nervous System / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D004347:Drug Interactions; D058785:GABA-A Receptor Agonists / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology* / Q000627:therapeutic use; D006801:Humans; D006993:Hypnotics and Sedatives / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology / Q000627:therapeutic use; D009474:Neurons / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D011963:Receptors, GABA-A / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D018686:Anesthetics, Intravenous; D014151:Anti-Anxiety Agents; D058785:GABA-A Receptor Agonists; D006993:Hypnotics and Sedatives; D011963:Receptors, GABA-A; D001569:Benzodiazepines; D005680:gamma-Aminobutyric Acid