''trans''-4-Hydroxycrotonic acid (T-HCA), also known as γ-hydroxycrotonic acid (GHC), is an

agent Agent may refer to: Espionage, investigation, and law *, spies or intelligence officers * Law of agency, laws involving a person authorized to act on behalf of another ** Agent of record, a person with a contractual agreement with an insuranc ...

used in scientific research to study the

GHB receptor The γ-hydroxybutyrate (GHB) receptor (GHBR), originally identified as GPR172A, is an excitatory G protein-coupled receptor (GPCR) that binds the neurotransmitter and psychoactive drug γ-hydroxybutyric acid (GHB). As solute carrier family 52 m ...

. It is an analogue of γ-hydroxybutyric acid (GHB), as well as an

active metabolite An active metabolite is an active form of a drug after it has been processed by the body. Metabolites of drugs An active metabolite results when a drug is metabolized by the body into a modified form which continues to produce effects in the body ...

of GHB. Similarly to GHB, T-HCA has been found to be

endogenous Endogenous substances and processes are those that originate from within a living system such as an organism, tissue, or cell. In contrast, exogenous substances and processes are those that originate from outside of an organism. For example, es ...

to the rat central nervous system, and as a metabolite of GHB, is almost certain to be endogenous to humans as well. T-HCA binds to the high-affinity GHB receptor with 4-fold greater affinity than GHB itself, where it acts as an

agonist An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the ago ...

, but does not bind to the low-affinity GHB binding site, the GABA_B receptor. Because of this, T-HCA does not produce

sedation Sedation is the reduction of irritability or agitation by administration of sedative drugs, generally to facilitate a medical procedure or diagnostic procedure. Examples of drugs which can be used for sedation include isoflurane, diethyl ether, ...

. T-HCA has been shown to cause receptor activation-evoked increases in extracellular

glutamate Glutamic acid (symbol Glu or E; the ionic form is known as glutamate) is an α-amino acid that is used by almost all living beings in the biosynthesis of proteins. It is a non-essential nutrient for humans, meaning that the human body can syn ...

concentrations, notably in the hippocampus.

References

Carboxylic acids Convulsants GHB receptor agonists Neurotransmitters {{nervous-system-drug-stub

See also

References