T-HCA

Not to be confused with Tetrahydrocannabinolic acid.

trans-4-Hydroxycrotonic acid (T-HCA), also known as γ-hydroxycrotonic acid (GHC), is an agent used in scientific research to study the GHB receptor.^[1] It is an analogue of γ-hydroxybutyric acid (GHB), as well as an active metabolite of GHB.^[2][3][4] Similarly to GHB, T-HCA has been found to be endogenous to the rat central nervous system, and as a metabolite of GHB, is almost certain to be endogenous to humans as well.^[3][5] T-HCA binds to the high-affinity GHB receptor with 4-fold greater affinity than GHB itself,^[6] where it acts as an agonist,^[1][7] but does not bind to the low-affinity GHB binding site, the GABA_B receptor.^[3][8] Because of this, T-HCA does not produce sedation. T-HCA has been shown to cause receptor activation-evoked increases in extracellular glutamate concentrations, notably in the hippocampus.^[8]

T-HCA

Clinical data
Other names	trans-4-hydroxycrotonic acid
ATC code	None
Identifiers
IUPAC name (2E)-4-hydroxybut-2-enoic acid
CAS Number	24587-49-3 Y
PubChem CID	6155526
ChemSpider	4825947 Y
UNII	NTM454U33F
ChEMBL	ChEMBL507046 Y
CompTox Dashboard (EPA)	DTXSID901027169
Chemical and physical data
Formula	C4H6O3
Molar mass	102.089 g·mol−1
3D model (JSmol)	Interactive image
SMILES O=C(O)\C=C\CO
InChI InChI=1S/C4H6O3/c5-3-1-2-4(6)7/h1-2,5H,3H2,(H,6,7)/b2-1+ Y Key:RMQJECWPWQIIPW-OWOJBTEDSA-N Y
NY (what is this?)  (verify)

See also

• HOCPCA
• γ-Crotonolactone