Differential effects of learning and recall of a spatial task on phosphoinositide hydrolysis induced by the metabotropic glutamate receptor agonist 1S,3R-ACPD (1S,3R-1-amino-cyclopentane-1,3-discarboxylic acid) in the hippocampus and the prefrontal cortex of rats.
Phosphoinositide (PI) hydrolysis, stimulated by 1S,3R-1-amino-cyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD), an agonist of metabotropic glutamate receptors (mGluRs), was measured in hippocampal and prefrontal cortical slices obtained from rats which had been trained for 8 days in a Morris water maze and had learned an allocentric spatial task. Brain slices were pre-labeled with myo-3H-inositol and 1S,3R-ACPD (100 microM) stimulation was assessed by measuring the accumulation of [3H]inositol phosphates ([3H]IPs) in the presence of Li+. Measurements conducted 24 h following the last training session revealed no differences in 1S,3R-ACPD-stimulated formation of [3H]IPs, either in the hippocampus or in the prefrontal cortex. However, a diminished response to mGluRs stimulation was detected in the hippocampus of animals re-trained after an 11-day interval. The decrease was not evident in the prefrontal cortex. These data indicate a differential involvement of the hippocampus and the prefrontal cortex in the processing of spatial information and correspond to the functional differences attributed to these areas.
de Bruin
J P
JP
Graduate School of Neurosciences Amsterdam, Netherlands Institute for Brain Research.
Facchinetti
F
F
Toth
E
E
Balazs
R
R
Joosten
R N
RN
D000818:Animals; D003515:Cycloleucine / Q000031:analogs & derivatives* / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism*; D006868:Hydrolysis; D008094:Lithium / Q000494:pharmacology; D008297:Male; D018782:Maze Learning / Q000187:drug effects / Q000502:physiology*; D011939:Mental Recall / Q000187:drug effects / Q000502:physiology*; D010716:Phosphatidylinositols / Q000378:metabolism*; D017397:Prefrontal Cortex / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D018094:Receptors, Metabotropic Glutamate / Q000187:drug effects / Q000378:metabolism*
D010716:Phosphatidylinositols; D018094:Receptors, Metabotropic Glutamate; D003515:Cycloleucine; C036361:1-amino-1,3-dicarboxycyclopentane; D008094:Lithium