LY367385 hydrochloride is a potent and selective mGluR1a antagonist with an IC50 value of 8.8 μM for inhibiting quisqualate-induced phosphoinositide (PI) hydrolysis, showing significantly higher selectivity compared to its >100 μM IC50 value for mGlu5a. This compound exhibits neuroprotective, anticonvulsant, and antiepileptic effects [1] [2].

LY367385 combined with N-methyl-D-aspartate (NMDA) during the toxic pulse attenuates neuronal degeneration in a concentration-dependent manner with a maximal reduction of NMDA toxicity ranging from 40 to 60%. LY367385 exhibits greater efficacy than LY367366 and neither of these compounds influenced neuronal viability per se. LY367385 shows potent neuroprotective effects, with leading a 50% reduction in (S)-3,5-Dihydroxyphenylglycine (DHPG) potentiation at a concentration of 10 nM. Under experimental conditions at higher concentrations of antagonist, LY367385 a completely antagonized the amplification of NMDA toxicity by DHPG [2].

LY367385 has been administered intracerebroventricularly (i.c.v.) to DBA/2 mice and lethargic mice (lh/lh), and focally into the inferior colliculus of genetically epilepsy prone rats (GEPR). In DBA/2 mice, LY367385 produces a rapid, transient inhibition of sound-induced clonic seizures ED50 = 12 nM, i.c.v., 5 min). In lethargic mice, LY367385 significantly reduces the incidence of spontaneous spike and wave discharges on the electroencephalogram, from 30 to >150 min after the administration of LY367385, 250 nM, i.c.v [3]. In genetically epilepsy prone rats, LY367385 reduces sound-induced clonic seizures. LY367385, 160 nM bilaterally, fully suppresses clonic seizures after 2-4 h [3].