Involvement of the posteroventral caudate-putamen in memory consolidation in the Morris water maze

Male Sprague-Dawley rats implanted with bilateral intracerebral guide cannu lae were trained in the standard hidden platform version of the Morris watt s maze and given immediate posttraining infusions of the D2 dopamine recept or antagonist sulpiride (10.0 or 100.0 ng/side) or saline vehicle into the posteroventral caudate-putamen. Retention was tested 2 days later with a pr obe trial. Sulpiride-treated rats spent less time swimming near the trained platform location and more time in the periphery of the maze than controls , although their latency to reach the trained platform location was not sig nificantly affected. The pattern of results suggests that whereas the poste roventral caudate-putamen seems to be involved in consolidation of memory i n the Morris water maze, it may be involved in memory for procedural aspect s of the task in a manner distinct from that of other brain regions such as the hippocampus. (C) 1999 Academic Press.