Involvement of the Cholinergic System in the Effects of DM-9384 on Carbon Monoxide (CO) -Induced Acute and Delayed Amnesia

Multi-infarct dementia (MID) may be caused from a deficiency in the supply of oxygen and glucose due to brain circulation insults. A transient ischemic attack is known to induce irreversible neuronal damage very slowly in the hippocampal CA1 subfield. “Delayed neuronal death” can also occur even after recovery from changes induced in biochemical and e1ectrophysiologic parameters due to ischemic insult (Take et al., 1984b). There is wide evidence showing that the cholinergic neuronal system is involved in the formation of memory function (Beninger et al., 1989; Newhouse, 1990), and thus the lower degree of the cholinergic neuronal function may be one mechanism of memory dysfunction following ischemic insult since it has been proved that cholinergic neuronal function is lower in ischemic rats than in control rats (Take at al., 1984a).