Systemic Administration of ?-Hydroxybutyric Acid in Adolescent Rat Impairs Contextual Fear Conditioning, But Not Cued Conditioning
Author(s): Ratna Sircar and Keita Ishiwari
γ-hydroxybutyric acid (GHB) causes retrograde amnesia in juveniles and young adults. Earlier, we have reported that in adolescent rat, GHB impairs the hidden platform task performance in the Morris water maze. In the present study, a classical fear conditioning paradigm was used to examine the effects of GHB on the acquisition of contextual conditioning, a hippocampus-dependent associative task, and cued tone conditioning, a hippocampus-independent task, in adolescent rats. Administration of GHB before the presentation of tone-shock pairings dose-dependently disrupted the acquisition of contextual conditioning with no effect on tone conditioning, when conditioned fear was measured 24 h later. Administering GHB prior to testing did not disrupt either contextual or tone conditioning. These results demonstrate that in the adolescent rat exposure to GHB preferentially disrupt hippocampal-dependent learning.