A New Cognition-Enhancing Agent, (R)-(-)-1-(Benzo [b] thiophen-5-yl)-2-[2-(N, N-diethylamino) ethoxy] ethanol Hydrochloride. Effects on Memory Impairment in Rats Generated by Cerebral Embolization and Basal Forebrain Lesions

Abstract

The title compound (T-588) has been evaluated for its ameliorating effect on memory impairment generated by cerebral embolization and by a basal forebrain (BF) lesion in male Wistar rats. The memory and learning deficits induced by injection of carbon-microspheres into the internal carotid artery were significantly improved by T-588 at oral dose of 3-10 mg/kg, as determined by an active avoidance response assay, whereas the reference drugs (tacrine, idebenone and indeloxazine) proved almost inactive in the same assay procedure. As far as the embolization was concerned, a significant decrease in cerebral acetylcholine and monoamines was observed. The effect on the memory impairment caused by an electrolytic lesion of the BF was assessed by a passive avoidance task. T-588 exhibited a bell-shaped dose-response curve and was most active at 1 mg/kg (oral dose), while tacrine showed equal activity at 10 mg/kg.