HexylHIBO is an antagonist of group I metabotropic glutamate receptors (mGluRs; Kbs = 140 and 110 ?M for mGluR1α and mGluR5a, respectively).1 It is selective for group I mGluRs over mGluR2 (group II) and mGluR4a (group III) (Kbs = >1,000 ?M for both), as well as AMPA, NMDA, and kainate receptors (IC50s = >100 ?M for all). HexylHIBO (6.3 and 12.5 mg/kg, i.c.v.) inhibits NMDA-induced seizures in mice. It also potentiates increases in plasma adrenocorticotropic hormone (ACTH) levels in a rat model of restraint stress.2
References:
[1]. Madsen, U., Br?uner-Osborne, H., Frydenvang, K., et al.Synthesis and pharmacology of 3-isoxazolol amino acids as selective antagonists at group I metabotropic glutamic acid receptorsJ. Med. Chem.44(7)1051-1059(2001).
[2]. Evanson, N.K., and Herman, J.P.Metabotropic glutamate receptor-mediated signaling dampens the HPA axis response to restraint stressPhysiol. Behav.1502-7(2015).