D-cycloserine, a partial NMDA receptor-associated glycine-B site agonist, enhances reversal learning, but a cholinesterase inhibitor and nicotine hasno effect

THE present study examined the efficacy of single and combined treatments w ith an anticholinesterase, tetrahydroaminoacridine, nicotine and a glycine- B site partial agonist, D-cycloserine, in alleviating the water maze revers al learning defect induced by a medial septal lesion. D-cycloserine (3 and 10 mg/kg) improved reversal learning. Tetrahydroaminoacridine (1 and 3 mg/k g) and nicotine (0.1 and 0.3 mg/kg) had no effect on reversal learning. A c ombination of tetrahydroaminoacridine 3 mg/kg or nicotine 0.3 mg/kg and D-c ycloserine 10 mg/kg was not more effective than D-cycloserine 10 mg/kg alon e in improving reversal learning. This suggests that stimulation of NMDA me chanisms may more effectively improve in medial septal-lesioned rats revers al learning processes than stimulation of cholinergic activity. NeuroReport 9: 3647-3651 (C) 1998 Lippincott Williams & Wilkins.