[Montirelin hydrate (NS-3), a TRH analog, improved disturbance of consciousness in cats: electroencephalographical studies].

Central effects of montirelin hydrate (NS-3) were electroencephalographically investigated in cats with experimentally induced disturbance of consciousness. All experiments were conducted under the gallamine-immobilized and artificially ventilated acute experimental condition. NS-3 and TRH produced EEG activation in cats with lesions in the midbrain reticular formation in a dose-dependent manner. Similar effects were observed in cats with bilateral lesions of the posterior hypothalamic area. These effects of NS-3 were 30 to 100 times more potent than those of TRH. NS-3 at doses higher than 0.003 mg/kg restored the suppressed EEG dose-dependently in cats with cerebral ischemia produced by clamping the bilateral common carotid arteries and basilar artery. TRH showed no effect at a dose of 10 mg/kg. These results indicate that NS-3 might be an effective drug for treating the disturbance of consciousness.