Effect on memory processing by D-cycloserine, an agonist of the NMDA/glycine receptor.
Glycine has been shown to modulate N-methyl-D-aspartate (NMDA) subclass of acidic amino acid receptors which have been implicated in learning and memory. We report that d-cycloserine (DCS) which has a high affinity for the glycine modulatory site in the NMDA receptor complex modulated memory processing in a dose-dependent manner. Mice were trained on a footshock avoidance task. Immediately after training DCS was administered (2.5 to 50 mg/kg s.c.). When retention was tested a week later, 20 mg/kg facilitated retention the best with lower and higher doses be less effective in weakly trained young mice. DCS also facilitated retention in 'senescence-accelerated mice' in which impairment of learning and memory increases with age. DCS had to be administered at higher doses to improve retention as impairment of learning and memory increased.
Flood
J F
JF
VA Medical Center, Geriatric Research Educational and Clinical Center, St. Louis, MO 63106.
Morley
J E
JE
Lanthorn
T H
TH
D000367:Age Factors; D000818:Animals; D003523:Cycloserine / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D008297:Male; D008568:Memory / Q000187:drug effects*; D051379:Mice; D018009:Receptors, Glycine; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects*; D017981:Receptors, Neurotransmitter / Q000187:drug effects*; D012153:Retention, Psychology / Q000187:drug effects
D018009:Receptors, Glycine; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter; D003523:Cycloserine