Intraventricular infusions of anti-neural cell adhesion molecules in a discrete posttraining period impair consolidation of a passive avoidance response in the rat.
Intraventricular infusions of anti-neural cell adhesion molecule (anti-NCAM) are demonstrated to inhibit consolidation of a passive avoidance response when administered in the 6-8 h posttraining period. Anti-NCAM was ineffective when administered during training or at any other time up to 10 h thereafter, and no amnesic effects were observed with absorbed anti-NCAM or anti-neurofilament protein. Amnesia was observed only at the 48-h recall time, and this could not be attributed to poor antibody penetration or a prolonged residence time, as studies with 125I-labelled anti-NCAM in trained animals demonstrated a rapid accumulation into all brain regions, and this was marked in the olfactory bulb and hippocampus, areas showing an inherent and paradigm-specific increase in NCAM sialylation state, respectively. The lack of an amnesic action at the 24-h recall time is attributed to anti-NCAM-impaired synapse structuring becoming apparent following the paradigm-specific increases in NCAM sialylation state.
Doyle
E
E
Department of Pharmacology, University College, Belfield, Dublin, Ireland.
Nolan
P M
PM
Bell
R
R
Regan
C M
CM
D000647:Amnesia / Q000209:etiology; D000818:Animals; D000906:Antibodies / Q000276:immunology / Q000502:physiology; D001362:Avoidance Learning / Q000502:physiology*; D001921:Brain / Q000378:metabolism; D015816:Cell Adhesion Molecules, Neuronal / Q000276:immunology / Q000502:physiology*; D007074:Immunoglobulin G / Q000276:immunology / Q000378:metabolism; D007158:Immunologic Techniques; D007276:Injections, Intraventricular; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D014018:Tissue Distribution
D000906:Antibodies; D015816:Cell Adhesion Molecules, Neuronal; D007074:Immunoglobulin G