The effect of dizocilpine (MK-801) on conditional discrimination learning in the rat.
The effect of the non-competitive N-methyl-D-aspartate (NMDA)-receptor antagonist, dizocilpine (MK-801) on the acquisition and reversal of conditional tasks was investigated using a Y-maze. Dizocilpine-treated rats were severely impaired on acquisition of a visuo-spatial task and were unable to learn the reversal of this task. 'Worse than chance' performance by dizocilpine-treated (and saline-treated) rats at the beginning of reversal testing, which was given 24 h after achieving criterion on acquisition, indicated that dizocilpine-treated animals simultaneously exhibited good memory but impaired learning for the type of information required for this task. Dizocilpine-treated rats were unable to acquire a visuo-visual conditional discrimination and therefore could not be assessed on reversal of this task. These very substantial impairments were larger than those found in comparable experiments using non-conditional tasks.
Murray
T K
TK
Astra Arcus AB, Södertälje, Sweden.
Ridley
R M
RM
D000818:Animals; D003213:Conditioning, Psychological; D004193:Discrimination Learning / Q000187:drug effects*; D016291:Dizocilpine Maleate / Q000494:pharmacology*; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology*; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D011597:Psychomotor Performance / Q000187:drug effects; D051381:Rats; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors
D018691:Excitatory Amino Acid Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D016291:Dizocilpine Maleate