RESUMEN
We developed new intravenous sedative-hypnotic compounds with the isoindolin-1-one skeleton focusing on the water-soluble property and in vivo safety. We synthesized approximately 170 derivatives and evaluated their hypnotic effects by intravenous administration of the compounds to mice. A series of the 2-phenyl-3-[2-(4-methyl-1-piperazinyl)-2-oxoethyl]isoindolin-1-one analogs, 3(-), 5(-), 27(-), and 47(-) [JM-1232(-)], showed potent sedative-hypnotic activity with good water solubility and a wide safety margin. The hypnotic doses (HD50s) of these 4 compounds when administered to mice were 2.35, 1.90, 2.17, and 3.12 mg/kg, respectively, and the lethal doses (LD50s) were 88.67, 64.69, >120, and >120 mg/kg, respectively. The therapeutic indexes (LD50/HD50) were 37.73, 34.05, >55.30, and >38.46, respectively. Among these compound, 47(-) [JM-1232(-)] is being considered as the most potential candidate for clinical trials in humans.
Asunto(s)
Hipnóticos y Sedantes , Isoindoles/farmacología , Animales , Fenómenos Químicos , Química Física , Inyecciones Intravenosas , Isoindoles/síntesis química , Isoindoles/toxicidad , Dosificación Letal Mediana , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Ratones Endogámicos ICR , Sueño/efectos de los fármacos , Solubilidad , EstereoisomerismoRESUMEN
Allodynia or hyperalgesia induced by peripheral nerve injury may be involved in changes in the sensitivity of neurotransmitters at the spinal cord level. In order to clarify the functional role of neurotransmitters in peripheral nerve injury, we used rats with nerve injury induced by chronic constriction of the sciatic nerve (CCI rat model) and estimated the effects of the intrathecal injection of drugs known to affect glutamate and tachykinin receptors. In sham-operated rats, the NMDA receptor agonist NMDA and AMPA-kinate receptor agonist RS-(5)-bromowillardin reduced withdrawal latency. The non-competitive NMDA receptor antagonist MK-801, competitive NMDA receptor antagonist AP-5 and AMPA-kinate receptor antagonist NBQX increased withdrawal latency. Substance P (SP) increased the withdrawal latency but only transitorily. The NK1 receptor antagonist RP67580 increased withdrawal latency, but the NK2 receptor antagonist SR48968 did not show an effect. In CCI rats, RS-(5)-bromowillardin reduced withdrawal latency, but NMDA did not show an effect. NBQX increased withdrawal latency, while MK-801 and AP-5 showed little or no effect. SP reduced withdrawal latency, and both RP67580 and SR48968 increased it. These results indicate that the alteration in sensitivity of ionotropic glutamate receptors and tachykinin receptors in the spinal cord contribute to development and maintenance of nerve injury-evoked neuropathic pain.